---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Thu 07/07/05: 43 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 05:11 AM - Re: Warning lights fro day VFR (Kevin Horton) 2. 05:30 AM - Re: Warning lights fro day VFR (rveighta) 3. 05:42 AM - Re: Warning lights fro day VFR (Dave Morris \) 4. 06:10 AM - Re: Warning lights fro day VFR (Robert L. Nuckolls, III) 5. 06:28 AM - Re: Warning lights fro day VFR (Ken) 6. 06:35 AM - Warning lights fro day VFR (need another cup of coffee!) (Robert L. Nuckolls, III) 7. 06:35 AM - Re: Z-14 ? (Robert L. Nuckolls, III) 8. 06:45 AM - Re: Z-14 ? (Robert L. Nuckolls, III) 9. 07:44 AM - DC fans problem. (Eric M. Jones) 10. 07:47 AM - Re: Re: Need a switch (Hinde, Frank George (Corvallis)) 11. 07:47 AM - ICOM PTT () 12. 07:59 AM - ICOM PTT () 13. 08:19 AM - Re: Re: Need a switch (BobsV35B@aol.com) 14. 09:21 AM - Re: Warning lights fro day VFR (Leo Corbalis) 15. 09:30 AM - Re: Re: Need a switch (Hinde, Frank George (Corvallis)) 16. 09:30 AM - Re: DC fans problem. (George Braly) 17. 09:39 AM - Re: Re: Need a switch (BobsV35B@aol.com) 18. 09:56 AM - Regulator output (Charlie Brame) 19. 09:56 AM - ICOM PTT (Charlie Brame) 20. 09:57 AM - Regulator output (Charlie Brame) 21. 10:45 AM - Multimeter problem (Paul Wilson) 22. 10:54 AM - Alternator output (Hinde, Frank George (Corvallis)) 23. 11:07 AM - Re: Regulator output (Craig P. Steffen) 24. 11:08 AM - Re: DC fans problem. (Eric M. Jones) 25. 11:38 AM - Re: DC fans problem. (Mickey Coggins) 26. 11:41 AM - Re: Warning lights fro day VFR (owner-aeroelectric-list-server@matronics.com) 27. 11:52 AM - Re: Alternator output (RV Builder (Michael Sausen)) 28. 12:03 PM - Re: Garmin 196 interferes with com radio () 29. 12:08 PM - Re: Multimeter problem (chad-c_sip@stanfordalumni.org) 30. 12:42 PM - Re: Re: Garmin 196 interferes with com radio (Mickey Coggins) 31. 12:47 PM - Re: DC fans problem. (Eric M. Jones) 32. 01:25 PM - Re: Regulator output (Robert L. Nuckolls, III) 33. 01:46 PM - Re: Re: Garmin 196 interferes with com radio (Cameron Kurth) 34. 02:21 PM - Re: Multimeter problem (Eric M. Jones) 35. 02:43 PM - Re: Multimeter problem (Dave Morris) 36. 03:21 PM - Re: DC fans problem. (Robert L. Nuckolls, III) 37. 03:56 PM - Re: Re: Multimeter problem (Paul Wilson) 38. 04:50 PM - Re: Re: Multimeter problem (chad-c_sip@stanfordalumni.org) 39. 05:29 PM - Re: Re: Multimeter problem (Joemotis@aol.com) 40. 05:59 PM - Re: ICOM PTT (Charlie England) 41. 05:59 PM - Alternator output (Robert L. Nuckolls, III) 42. 06:31 PM - Re: ICOM PTT (Ken) 43. 07:03 PM - Re: Re: Multimeter problem (John D. Heath) ________________________________ Message 1 _____________________________________ Time: 05:11:19 AM PST US From: Kevin Horton Subject: Re: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: Kevin Horton On 7 Jul 2005, at 02:36, Michle Delsol wrote: > --> AeroElectric-List message posted by: > > Folks, > > > Could some of you guys recommend warning lights to put on the > panel? My > objective is to have bright lights therefore visible in direct > sunlight. > LEDs could probably do it better than incandescent bulbs. Since I > shall not > be doing night VFR or IFR as most of Europe does not allow it with > experimentals (unless the engine and avionics are certified and > maintained > as a certified), I would not need a dimmer circuit. > > Michle, The large red LED that comes with the Grand Rapids EIS is very bright, and quite visible in sunlight. The same lamp comes in green, available at Newark Electronics, part numbers: 52F9235 Green LED http://www.newark.com/NewarkWebCommerce/newark/ en_US/endecaSearch/partDetail.jsp?SKU=52F9235&N=0 52F9237 Red LED http://www.newark.com/NewarkWebCommerce/newark/en_US/ endecaSearch/partDetail.jsp?SKU=52F9237&N=0 Newark also used to carry the amber version, part number 52F9239, but their web site no longer admits any knowledge of this one. These red LEDs are quite bright. The amber and green are a bit less bright. I originally planned to use them, but eventually found a good price on used Vivisun annunciators. You can get an idea of what these LEDs look like from the picture of when I had them in my panel: http://www.kilohotel.com/rv8/article.php?story=20040418195119749 Kevin Horton RV-8 (finishing kit) Ottawa, Canada http://www.kilohotel.com/rv8 ________________________________ Message 2 _____________________________________ Time: 05:30:02 AM PST US From: rveighta Subject: Re: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: rveighta Michele, I agree with Kevin Horton regarding the Grand Rapids engine monitor. I might add that the warning light blinks on and off until you acknowledge the problem by pushing the "ack" button, whereupon it displays a steady red. I have been flying an RV-8A for two years with this set-up and highly recommend it. I have also installed Van's hour meter in my new RV-8 which has a red light which comes on when you activate the master switch until it senses oil pressure from engine start. This serves a a good reminder to turn the master off after a flight. Walt Shipley -----Original Message----- From: owner-aeroelectric-list-server@matronics.com Subject: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: Folks, Could some of you guys recommend warning lights to put on the panel? My objective is to have bright lights therefore visible in direct sunlight. LEDs could probably do it better than incandescent bulbs. Since I shall not be doing night VFR or IFR as most of Europe does not allow it with experimentals (unless the engine and avionics are certified and maintained as a certified), I would not need a dimmer circuit. Thanks, Mich=E8le Delsol RV8 Fuselage (working on first assembly of the dreaded gear boxes). ________________________________ Message 3 _____________________________________ Time: 05:42:09 AM PST US From: "Dave Morris \"BigD\"" Subject: Re: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: "Dave Morris \"BigD\"" There's always this: http://www.aircraftsimulators.com/f18cautlts.html They will create a custom panel for you, pretty cheap. Add a warning tone for maximum alert. Dave Morris At 01:36 AM 7/7/2005, you wrote: >--> AeroElectric-List message posted by: > >Folks, > > >Could some of you guys recommend warning lights to put on the panel? My >objective is to have bright lights therefore visible in direct sunlight. >LEDs could probably do it better than incandescent bulbs. Since I shall not >be doing night VFR or IFR as most of Europe does not allow it with >experimentals (unless the engine and avionics are certified and maintained >as a certified), I would not need a dimmer circuit. > > >Thanks, > >Mich=E8le Delsol > >RV8 Fuselage (working on first assembly of the dreaded gear boxes). > > ________________________________ Message 4 _____________________________________ Time: 06:10:29 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > >I have been flying an RV-8A for two years with this set-up and highly >recommend >it. I have also installed Van's hour meter in my new RV-8 which has a red >light >which comes on when you activate the master switch until it senses oil >pressure >from engine start. This serves a a good reminder to turn the master off >after a >flight. Active notification of low bus voltage will also help you forget to turn of the battery master. Bob . . . ________________________________ Message 5 _____________________________________ Time: 06:28:32 AM PST US From: Ken Subject: Re: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: Ken FWIW the indicator that came with my EIS was incandescent not an LED although it looks identical externally. I agree with soldering wires to it rather than using the supplied push on PIDG terminals. The bulb is potted in epoxy and connected with solid wires which means that after a couple of wiggles the wire to the terminal breaks. Mine also drew about 100 ma at 12 volts rather than the 35 shown at http://www.imlec.com/indicators/model1501.pdf Might have been a custom extra bright indicator... For one of my indicators I potted a large 10mm 12volt red and green alternating flashing LED in a round aluminum bezel. It's an attention getter... Ken Kevin Horton wrote: >--> AeroElectric-List message posted by: Kevin Horton > >On 7 Jul 2005, at 02:36, Michle Delsol wrote: > > > >>--> AeroElectric-List message posted by: >> >>Folks, >> >> >>Could some of you guys recommend warning lights to put on the >>panel? My >>objective is to have bright lights therefore visible in direct >>sunlight. >>LEDs could probably do it better than incandescent bulbs. Since I >>shall not >>be doing night VFR or IFR as most of Europe does not allow it with >>experimentals (unless the engine and avionics are certified and >>maintained >>as a certified), I would not need a dimmer circuit. >> >> >> >> > >Michle, > >The large red LED that comes with the Grand Rapids EIS is very >bright, and quite visible in sunlight. The same lamp comes in green, >available at Newark Electronics, part numbers: > >52F9235 Green LED http://www.newark.com/NewarkWebCommerce/newark/ >en_US/endecaSearch/partDetail.jsp?SKU=52F9235&N=0 >52F9237 Red LED http://www.newark.com/NewarkWebCommerce/newark/en_US/ >endecaSearch/partDetail.jsp?SKU=52F9237&N=0 > >Newark also used to carry the amber version, part number 52F9239, but >their web site no longer admits any knowledge of this one. > >These red LEDs are quite bright. The amber and green are a bit less >bright. I originally planned to use them, but eventually found a >good price on used Vivisun annunciators. > >You can get an idea of what these LEDs look like from the picture of >when I had them in my panel: > >http://www.kilohotel.com/rv8/article.php?story=20040418195119749 > >Kevin Horton RV-8 (finishing kit) >Ottawa, Canada >http://www.kilohotel.com/rv8 > > > > ________________________________ Message 6 _____________________________________ Time: 06:35:19 AM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Warning lights fro day VFR (need another cup of coffee!) --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 08:09 AM 7/7/2005 -0500, you wrote: >--> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > > > > > > >I have been flying an RV-8A for two years with this set-up and highly > >recommend > >it. I have also installed Van's hour meter in my new RV-8 which has a red > >light > >which comes on when you activate the master switch until it senses oil > >pressure > >from engine start. This serves a a good reminder to turn the master off > >after a > >flight. > > Active notification of low bus voltage will also help > you forget to turn of the battery master. . . . of course this should read "help you AVOID forgetting to turn off the battery master." Bob . . . ________________________________ Message 7 _____________________________________ Time: 06:35:40 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Z-14 ? --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 09:59 PM 7/6/2005 -0400, you wrote: >--> AeroElectric-List message posted by: TimRhod@aol.com > >Bob: On your Z-14 diagram you show a primary fuel pump on the main >battery bus and a secondary fuel pump on the auxiliary battery bus. Is >this two >sources of power to the same fuel pump? If yes this solves my problem. >Tonight I went out to start my plane and I had left the main master on over >night. main battery dead of course. Aux battery fine but right now I >only have >the electric fuel pump wired to the main battery buss so no fuel pump and >crossfeed doesn't help. Engine would crank but without fuel pump no >start. Two >solutions I considered 1. two battery sources to fuel pump, therefore my >question above or 2. move the fuel pump wire to Main or >Aux bus. Thanks >Tim Rhodenbaugh > > >-- > > >-- incoming mail is certified Virus Free. Bob . . . -------------------------------------------------------- < Throughout history, poverty is the normal condition > < of man. Advances which permit this norm to be > < exceeded -- here and there, now and then -- are the > < work of an extremely small minority, frequently > < despised, often condemned, and almost always opposed > < by all right-thinking people. Whenever this tiny > < minority is kept from creating, or (as sometimes > < happens) is driven out of a society, the people > < then slip back into abject poverty. > < > < This is known as "bad luck". > < -Lazarus Long- > <------------------------------------------------------> http://www.aeroelectric.com ________________________________ Message 8 _____________________________________ Time: 06:45:09 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Z-14 ? --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 09:59 PM 7/6/2005 -0400, you wrote: >--> AeroElectric-List message posted by: TimRhod@aol.com > >Bob: On your Z-14 diagram you show a primary fuel pump on the main >battery bus and a secondary fuel pump on the auxiliary battery bus. Is >this two >sources of power to the same fuel pump? It's what ever you need it to be. Z-14 and its brothers are simply examples of architecturs where you can mix/match features between them. If you have two fuel pumps, then running each from opposite sides of Z-14 makes sense. If you have one fuel pump, then perhaps diode isolated feeds from both sides to the same pump makes sense. > If yes this solves my problem. >Tonight I went out to start my plane and I had left the main master on over >night. main battery dead of course. Aux battery fine but right now I >only have >the electric fuel pump wired to the main battery buss so no fuel pump and >crossfeed doesn't help. Engine would crank but without fuel pump no >start. Two >solutions I considered 1. two battery sources to fuel pump, therefore my >question above or 2. move the fuel pump wire to Main or Aux bus. Your note illuminates what we might call a "problem" area with Z-14 or ANY two-battery system. If the battery has been depleted to dead-Dead-DEAD then you cannot use it to get it's own contactor closed even if the other battery will still get the airplane started . . . and everything on the DEAD battery bus remains un-powered and the dead battery cannot be recharged from the ship's alternator. One might consider using the S701-2 CROSSFEED contactor arrangement as a battery contactor. The two-diode feed to the top of the coil would allow the contactor to close using energy from EITHER the battery or bus side of contactor. Assuming the charged battery is capable of cranking the engine, then this re-wiring of the contactor will prevent a reoccurrence of the scenario you've described. Bob . . . ________________________________ Message 9 _____________________________________ Time: 07:44:44 AM PST US From: "Eric M. Jones" Subject: AeroElectric-List: DC fans problem. --> AeroElectric-List message posted by: "Eric M. Jones" A customer of mine bought a solid state relay from me but it failed when driving a small DC fan. This certainly does not speak well of the ruggedness of the solid state device. It is based on the International Rectifier IPS5551T with a few added features and additional EMI protection. I test these things at 60 Amps. Examining the SSR didn't help much except to show that the chip was toast and that it probably didn't fail from current (usually current failures show cracked cases). Besides the thing has overcurrent and overtemp protection. This was a mystery that took far too long to solve...but finally I checked the whole circuit and found that when a DC fan is turned off, it becomes a power generator for at least a few seconds, and the voltage output (no load!) can easily exceed the specs of the SSR. So I offer this interesting information. Lots of devices have DC fans and solid state parts. The devil is in the details. Make sure you put a Transient Voltage Suppressor across every DC fan and every relay and coil and motor unless an oscilloscope says you don't need to. By the way--The output voltage transient in this case was in the same polarity as the applied voltage--so a diode wouldn't do anything. The peak voltage spikes exceeded 30V on a very small 2.6W 12V DC fan. Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 When trouble arises and things look bad, there is always one individual who perceives a solution and is willing to take command. Very often, that individual is crazy. --Dave Barry ________________________________ Message 10 ____________________________________ Time: 07:47:21 AM PST US Subject: RE: AeroElectric-List: Re: Need a switch From: "Hinde, Frank George (Corvallis)" --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" Or just run both ignitions all the time...I hear lot of debabte about whether this is a good idea or not but I never saw a coil joiner or other component that failed due to running like this. Frank HDS Subaru -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Jim and Lucy Subject: Re: AeroElectric-List: Re: Need a switch --> AeroElectric-List message posted by: Jim and Lucy --> At 10:08 PM 7/6/2005, you wrote: >Something to think about - if one ignition fails, and you then select >the other ignition on, the engine will have been pushing unburnt fuel >into the exhaust. There is a good chance you will have a very large >backfire, That is a good thing to think about that I had not got to yet. ________________________________ Message 11 ____________________________________ Time: 07:47:27 AM PST US From: Subject: AeroElectric-List: ICOM PTT --> AeroElectric-List message posted by: AeroElectric-List message previously posted by: Charlie England ceengland@bellsouth.net >AeroElectric-List message posted by: bakerocb@cox.net >.....skip.......My question is: Can I instead use my standard push-to-talk >switch, with the >larger diameter sized microphone receptacle and plug such as David Clark >and >Telex sell, in line with the microphone plug from the headset to the >OPC-752 >Adapter to key the IC-A4 transmitter?......skip Plug in the headset adaptor, turn on the radio & push the side mounted xmit button. Does the xmit led light up? My IC-A4 works fine using the adaptor & the regular xmit button. My manual says the radio won't work while on the external charge jack (exactly opposite what the ICOM rep promised me before I bought it). Charlie 7/7/2005 Hello Charlie, Thanks for your input and suggestion -- I will try that. But lighting up a light is no absolute guarantee that you are transmitting a signal. Only using a separate receiver and receiving a signal would guarantee that -- I am a skeptical type. I agree that there are some misleading / incorrect statements in the manual, but I think some caution is in order in interpreting or rejecting them. Here are two extracts from my manual: "EXTERNAL DC POWER JACK [CHARGE]Connect a 12 to 16 V DC power source using the optional cables, CP-12L or OPC-254L, to charge the attached battery pack; or connect the BC-110V wall charger for charging. CAUTION:This connection is for charging ONLY. Power to the transceiver must be turned OFF during charging." ..... "CP-12L CIGARETTE LIGHTER CABLE WITH NOISE FILTER Allows you to charge a battery pack connected to the transceiver via a DC power source (12-16 V DC) For charging ONLY-the transceiver cannot be simultaneously operated." I was researching something on the IC-A4 earlier and was told by some authoritative source (can't recall who now) that: Yes, the radio would work when you are providing DC power to the external DC power jack, but the radio is designed to operate on 9.6 volts DC -- the output from a normal battery pack. If instead you try to operate the radio when some higher DC voltage is being applied to the external DC power jack you run the risk of damaging the radio. No specific information on just how high that higher DC voltage has to be coming into the external DC power jack in order to damage the radio while attemping to operate it, but caution would be in order. OC ________________________________ Message 12 ____________________________________ Time: 07:59:53 AM PST US From: Subject: AeroElectric-List: ICOM PTT --> AeroElectric-List message posted by: AeroElectric-List message previouslyposted by: "Lloyd, Daniel R." Can you put your primary radio on speaker and stand outside the plane and talk into the handheld and see if the plane receives it? 7/7/2005 Hello Lloyd, Thanks for your suggestion, but I built my KIS TR-1 with no speaker. I have headset operations only. I did try something similar by attempting to transmit with my IC-A4 to my Sporty's Air Scan V radio, but only generated a squeal. I assumed that I was too close and over powering the Sporty's radio receiver. This left me still uncertain of my IC-A4's capability in regard to using a standard push to talk button. OC ________________________________ Message 13 ____________________________________ Time: 08:19:35 AM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Re: Need a switch --> AeroElectric-List message posted by: BobsV35B@aol.com Good Morning Frank, My knowledge of power plant engineering is minimal, but I am aware that a normal certificated aircraft engine is affected by using only one mag to provide ignition. Operating on one magneto effectively retards the spark. Do the electronic ignition systems automatically adjust themselves to accommodate the change in timing that results from using only one ignition source? Do Not Archive Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Airpark LL22 Downers Grove, IL 60516 630 985-8502 In a message dated 7/7/2005 9:48:42 A.M. Central Standard Time, frank.hinde@hp.com writes: Or just run both ignitions all the time...I hear lot of debate about whether this is a good idea or not but I never saw a coil joiner or other component that failed due to running like this. Frank HDS Subaru ________________________________ Message 14 ____________________________________ Time: 09:21:29 AM PST US From: "Leo Corbalis" Subject: Re: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: "Leo Corbalis" I thought that the light was enough too. I had to wait a week for my second flight. I didn't see the red light ON with the sun in my face and ran the battery FLAT over the weekend. (wife comes first) and I had get a new one. I added a simple piezo beeper in paralell with the light. Get one that is on continueously when the power is on, you don't want two differient timers trying to control the beep. Haven't forgotten the master sw. since then. Leo Corbalis ----- Original Message ----- From: "rveighta" Subject: Re: AeroElectric-List: Warning lights fro day VFR > --> AeroElectric-List message posted by: rveighta > > > Michele, I agree with Kevin Horton regarding the Grand Rapids engine > monitor. > I might add that the warning light blinks on and off until you acknowledge > the > problem by pushing the "ack" button, whereupon it displays a steady red. > > I have been flying an RV-8A for two years with this set-up and highly > recommend > it. I have also installed Van's hour meter in my new RV-8 which has a red > light > which comes on when you activate the master switch until it senses oil > pressure > from engine start. This serves a a good reminder to turn the master off > after a > flight. > > Walt Shipley > > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com > To: aeroelectric-list@matronics.com > Subject: AeroElectric-List: Warning lights fro day VFR > > --> AeroElectric-List message posted by: > > Folks, > > > Could some of you guys recommend warning lights to put on the panel? My > objective is to have bright lights therefore visible in direct sunlight. > LEDs could probably do it better than incandescent bulbs. Since I shall > not > be doing night VFR or IFR as most of Europe does not allow it with > experimentals (unless the engine and avionics are certified and maintained > as a certified), I would not need a dimmer circuit. > > > Thanks, > > Mich=E8le Delsol > > RV8 Fuselage (working on first assembly of the dreaded gear boxes). > > > ________________________________ Message 15 ____________________________________ Time: 09:30:40 AM PST US Subject: RE: AeroElectric-List: Re: Need a switch From: "Hinde, Frank George (Corvallis)" --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" Good morning to you too Bob. This is true for a proper aircraft engine because of the large bore the flame front has to travel across and the fact there are two spark plugs...In other words the flame is lit from both sides and only has to travel half the distance than if one of the plugs is fireing. In an auto engine such as the Subaru there is only one spark plug and the two ignition systems are joined together with high voltage diodes before they get to this single spark plug. In theory therefore running either one or both systems makes no difference to the effective timing of the engine. Frank Do not archive -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of BobsV35B@aol.com Subject: Re: AeroElectric-List: Re: Need a switch --> AeroElectric-List message posted by: BobsV35B@aol.com Good Morning Frank, My knowledge of power plant engineering is minimal, but I am aware that a normal certificated aircraft engine is affected by using only one mag to provide ignition. Operating on one magneto effectively retards the spark. Do the electronic ignition systems automatically adjust themselves to accommodate the change in timing that results from using only one ignition source? Do Not Archive Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Airpark LL22 Downers Grove, IL 60516 630 985-8502 In a message dated 7/7/2005 9:48:42 A.M. Central Standard Time, frank.hinde@hp.com writes: Or just run both ignitions all the time...I hear lot of debate about whether this is a good idea or not but I never saw a coil joiner or other component that failed due to running like this. Frank HDS Subaru ________________________________ Message 16 ____________________________________ Time: 09:30:51 AM PST US Subject: RE: AeroElectric-List: DC fans problem. From: "George Braly" --> AeroElectric-List message posted by: "George Braly" Was it wired up as a high side or a low side switch to the DC Fan motor ? George -----Original Message----- From: owner-aeroelectric-list-server@matronics.com [mailto:owner-aeroelectric-list-server@matronics.com] On Behalf Of Eric M. Jones Subject: AeroElectric-List: DC fans problem. --> AeroElectric-List message posted by: "Eric M. Jones" A customer of mine bought a solid state relay from me but it failed when driving a small DC fan. This certainly does not speak well of the ruggedness of the solid state device. It is based on the International Rectifier IPS5551T with a few added features and additional EMI protection. I test these things at 60 Amps. Examining the SSR didn't help much except to show that the chip was toast and that it probably didn't fail from current (usually current failures show cracked cases). Besides the thing has overcurrent and overtemp protection. This was a mystery that took far too long to solve...but finally I checked the whole circuit and found that when a DC fan is turned off, it becomes a power generator for at least a few seconds, and the voltage output (no load!) can easily exceed the specs of the SSR. So I offer this interesting information. Lots of devices have DC fans and solid state parts. The devil is in the details. Make sure you put a Transient Voltage Suppressor across every DC fan and every relay and coil and motor unless an oscilloscope says you don't need to. By the way--The output voltage transient in this case was in the same polarity as the applied voltage--so a diode wouldn't do anything. The peak voltage spikes exceeded 30V on a very small 2.6W 12V DC fan. Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 When trouble arises and things look bad, there is always one individual who perceives a solution and is willing to take command. Very often, that individual is crazy. --Dave Barry --- --- ________________________________ Message 17 ____________________________________ Time: 09:39:25 AM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: Re: Need a switch --> AeroElectric-List message posted by: BobsV35B@aol.com In a message dated 7/7/2005 11:31:47 A.M. Central Standard Time, frank.hinde@hp.com writes: In an auto engine such as the Subaru there is only one spark plug and the two ignition systems are joined together with high voltage diodes before they get to this single spark plug. In theory therefore running either one or both systems makes no difference to the effective timing of the engine. Thank You Frank, I had no idea that anyone was running two ignitions to fire the same plug! Do Not Archive Happy Skies, Old Bob AKA Bob Siegfried Ancient Aviator Stearman N3977A Brookeridge Airpark LL22 Downers Grove, IL 60516 630 985-8502 ________________________________ Message 18 ____________________________________ Time: 09:56:20 AM PST US From: Charlie Brame Subject: AeroElectric-List: Regulator output --> AeroElectric-List message posted by: Charlie Brame Bob, et. al., The electrical system in my RV-6A is configured very close to Bob's Z-13, All Electric on a Budget. I have a B&C alternator and a Ford equivalent regulator which is adjustable and bench set to 13.8 volts. With the main contactor off and using the essential bus only, I show about 13.5 volts at the bus. However, when using the normal system with the essential bus powered through a diode, the essential bus only shows 12.8 volts. This is understandable considering the loss through the contactor and the diode. My avionics and my gyros (ADI and DG) are connected via the essential bus and I wonder if a higher voltage would improve both radio and gyro perfomance somewhat. My question is: should I up the regulator voltage in order to get close to 13.8 volts at the essential bus when using the main or normal system? This would result in 14+ volts on the main bus, but that shouldn't adversely affect anything, IMHO. Charlie RV-6A N11CB San Antonio ________________________________ Message 19 ____________________________________ Time: 09:56:47 AM PST US From: Charlie Brame Subject: AeroElectric-List: ICOM PTT --> AeroElectric-List message posted by: Charlie Brame I can't speak to the ICOM IC-A4. I have an ICOM IC-A23 which I also use as a comm backup. With my headset plugged into the A23, the side button PTT works as advertised - i.e., it transmits with a good side tone. I can also plug in a separate PTT switch which works just as well. My headset adapter is an ICOM product, but the separate PTT switch is an off brand item. Charlie RV-6A N11CB San Antonio ------------------------------ > Time: 10:03:22 AM PST US > From: > Subject: AeroElectric-List: ICOM PTT > > --> AeroElectric-List message posted by: > > 7/6/2005 > > Hello Experts, I have an ICOM IC-A4 hand held radio that I carry in my > airplane as a communications back up. I also have the ICOM OPC-752 Headset > Adapter cable accessory, but I do not have the separate ICOM 3.5 mm diameter > PTT switch accessory for keying the transmitter while using the radio with > that adapter and a headset. The manual says that the transmitter keying > button on the side of the radio will not work when the headset adapter is > plugged in. > > According to a diagram in the ICOM IC-A4 manual the ICOM PTT switch simply > connects the tip of the microphone plug to the shank of the microphone plug > in order to key the IC-A4 transmitter. > > My question is: Can I instead use my standard push-to-talk switch, with the > larger diameter sized microphone receptacle and plug such as David Clark and > Telex sell, in line with the microphone plug from the headset to the OPC-752 > Adapter to key the IC-A4 transmitter? > > ICOM refuses to answer this question for me by saying they won't comment on > any one else's equipment. Thanks. > > OC > > ________________________________ Message 20 ____________________________________ Time: 09:57:56 AM PST US From: Charlie Brame Subject: AeroElectric-List: Regulator output --> AeroElectric-List message posted by: Charlie Brame Bob, et. al., The electrical system in my RV-6A is configured very close to Bob's Z-13, All Electric on a Budget. I have a B&C alternator and a Ford equivalent regulator which is adjustable and bench set to 13.8 volts. With the main contactor off and using the essential bus only, I show about 13.5 volts at the bus. However, when using the normal system with the essential bus powered through a diode, the essential bus only shows 12.8 volts. This is understandable considering the loss through the contactor and the diode. My avionics and my gyros (ADI and DG) are connected via the essential bus and I wonder if a higher voltage would improve both radio and gyro perfomance somewhat. My question is: should I up the regulator voltage in order to get close to 13.8 volts at the essential bus when using the main or normal system? This would result in 14+ volts on the main bus, but that shouldn't adversely affect anything, IMHO. Charlie RV-6A N11CB San Antonio ________________________________ Message 21 ____________________________________ Time: 10:45:49 AM PST US From: Paul Wilson Subject: AeroElectric-List: Multimeter problem --> AeroElectric-List message posted by: Paul Wilson I have 3 digital multimeters that do not agree at all. Unfortunately I posted some battery voltages on a large automotive AGM Optima battery that are now highly suspect. On the battery which was freshly charged: 1) GB Instruments GDT-11 bought at Home Depot about 2 months ago 12.80v, same with new 9v battery 2) Radio Shack Auto ranging # 22-163, about 2 years old 12.55v same with new AA cells 3) Radio Shack # 22-191, 8-10 years old 12.69v same with new AA cells. Way to much difference to tell the state of charge of this relatively new battery. How can I tell which units are reading correct voltages? Is there a test I can perform? Thanks, Paul ________________________________ Message 22 ____________________________________ Time: 10:54:58 AM PST US Subject: AeroElectric-List: Alternator output From: "Hinde, Frank George (Corvallis)" --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" So my all elctric IFR plane (no mech fuel pump) will have main alt and an SD-8 for backup. My question is around failure detection. It seems to me NOT to be a good idea to rely on voltage reduction to detect an alternator failure, because it may take a while for the volts to dip if at all. A much better way would appear to be to use the Dynon engine management system to measure current from the alternator and to set an alarm below the minimum day VFR loads...This alarm would send an audio tone thru my headset... This method should work fine if I only had one alternator...with the SD-8 I have 2 and the current may not drop that low because the min day VFR could be a s low as 7 to 8 amps, depending on voltage the Main alt may only be generating a couple of amps and a failure difficult to detect. An alternative would be not to run the SD-8 unless I had to...I.e keep it switched off...if the main alt dies or trips on OV I get a low current alarm...Then bang on the SD-8 and start load managing. Any flaw in the logic here?...Can I switch an SD-8 like this? Thanks Frank ________________________________ Message 23 ____________________________________ Time: 11:07:14 AM PST US Subject: Re: AeroElectric-List: Regulator output From: "Craig P. Steffen" --> AeroElectric-List message posted by: "Craig P. Steffen" First of all: I HAVE NO KNOWLEDGE OF THE SAFETY, PRACTICALITY OR LEGALITY OF ISOLATOR DIODES IN AIRCRAFT. That having been said, > The electrical system in my RV-6A is configured very close to Bob's > Z-13, All Electric on a Budget. I have a B&C alternator and a Ford > equivalent regulator which is adjustable and bench set to 13.8 volts. > With the main contactor off and using the essential bus only, I show > about 13.5 volts at the bus. However, when using the normal system with > the essential bus powered through a diode, the essential bus only shows > 12.8 volts. This is understandable considering the loss through the > contactor and the diode. If memory of my electronics course serves, a silicon diode has a forward voltage drop of between .6 and .7 V, which accounts for the voltage on your essential bus. Also if memory serves, the forward voltage drop of a germanium diode is .3V. The DISadvantage of germanium diodes is that they have a reverse leakage current much higher than silicon diodes, in the milliamp range vs. the micro-amp range for silicon. I don't know how hard germanium diodes are to get, or if you could get one of the proper rating at all. Remember, it has to be large enough to dissipate the current powering the essential bus when the alternator is working properly ( .3V * max_essential_bus_current ). Just a thought, from the electronics side of things. Craig Steffen -- craig@craigsteffen.net public key available at http://www.craigsteffen.net/GPG/ current goal: use a CueCat scanner to inventory my books career goal: be the first Vorlon Time Lord ________________________________ Message 24 ____________________________________ Time: 11:08:20 AM PST US From: "Eric M. Jones" Subject: AeroElectric-List: RE: DC fans problem. --> AeroElectric-List message posted by: "Eric M. Jones" Subject: From: George Braly (gwbraly@gami.com) --> AeroElectric-List message posted by: "George Braly" >Was it wired up as a high side or a low side switch to the DC Fan motor? >George George, It was configured as a high side switch. See http://www.irf.com/product-info/datasheets/data/ips5551t.pdf Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 Teamwork: " A lot of people doing exactly what I say." (Marketing exec., Citrix Corp.) ________________________________ Message 25 ____________________________________ Time: 11:38:22 AM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: DC fans problem. --> AeroElectric-List message posted by: Mickey Coggins > ... Make sure you put > a Transient Voltage Suppressor across every DC fan and every relay > and coil and motor unless an oscilloscope says you don't need to. Hi Eric, What would be the part number for that Transient Voltage Suppressor? Do you sell them with a pretty picture like you have for the rest of your stuff? Thanks, Mickey -- Mickey Coggins http://www.rv8.ch/ #82007 finishing ________________________________ Message 26 ____________________________________ Time: 11:41:39 AM PST US From: owner-aeroelectric-list-server@matronics.com Subject: RE: AeroElectric-List: Warning lights fro day VFR --> AeroElectric-List message posted by: Thanks guys - as usual you all are priceless - part of the fun of building is this list. DO NOT ARCHIVE Michele Delsol RV8 - Fuselage > -----Original Message----- > From: owner-aeroelectric-list-server@matronics.com [mailto:owner- > aeroelectric-list-server@matronics.com] On Behalf Of Leo Corbalis > Sent: Thursday, July 07, 2005 6:18 PM > To: aeroelectric-list@matronics.com > Subject: Re: AeroElectric-List: Warning lights fro day VFR > Importance: High > > --> AeroElectric-List message posted by: "Leo Corbalis" > > > I thought that the light was enough too. I had to wait a week for my > second > flight. I didn't see the red light ON with the sun in my face and ran the > battery FLAT over the weekend. (wife comes first) and I had get a new one. > I > added a simple piezo beeper in paralell with the light. Get one that is on > continueously when the power is on, you don't want two differient timers > trying to control the beep. Haven't forgotten the master sw. since then. > > Leo Corbalis > > ----- Original Message ----- > From: "rveighta" > To: > Subject: Re: AeroElectric-List: Warning lights fro day VFR > > > > --> AeroElectric-List message posted by: rveighta > > > > > > > Michele, I agree with Kevin Horton regarding the Grand Rapids engine > > monitor. > > I might add that the warning light blinks on and off until you > acknowledge > > the > > problem by pushing the "ack" button, whereupon it displays a steady red. > > > > I have been flying an RV-8A for two years with this set-up and highly > > recommend > > it. I have also installed Van's hour meter in my new RV-8 which has a > red > > light > > which comes on when you activate the master switch until it senses oil > > pressure > > from engine start. This serves a a good reminder to turn the master off > > after a > > flight. > > > > Walt Shipley > > > > -----Original Message----- > > From: owner-aeroelectric-list-server@matronics.com > > To: aeroelectric-list@matronics.com > > Subject: AeroElectric-List: Warning lights fro day VFR > > > > --> AeroElectric-List message posted by: > > > > Folks, > > > > > > Could some of you guys recommend warning lights to put on the panel? My > > objective is to have bright lights therefore visible in direct sunlight. > > LEDs could probably do it better than incandescent bulbs. Since I shall > > not > > be doing night VFR or IFR as most of Europe does not allow it with > > experimentals (unless the engine and avionics are certified and > maintained > > as a certified), I would not need a dimmer circuit. > > > > > > Thanks, > > > > Mich=E8le Delsol > > > > RV8 Fuselage (working on first assembly of the dreaded gear boxes). > > > > > > > > > > > ________________________________ Message 27 ____________________________________ Time: 11:52:10 AM PST US Subject: RE: AeroElectric-List: Alternator output From: "RV Builder (Michael Sausen)" --> AeroElectric-List message posted by: "RV Builder (Michael Sausen)" I believe B&C sells a regulator specifically to keep the backup alternator offline until the bus voltage drops below a specific point. This is probably what you want. Someone else can chime in with the part specifics. Michael Sausen -10 #352 Tailcone ________________________________ From: owner-aeroelectric-list-server@matronics.com on behalf of Hinde, Frank George (Corvallis) Subject: AeroElectric-List: Alternator output --> AeroElectric-List message posted by: "Hinde, Frank George (Corvallis)" So my all elctric IFR plane (no mech fuel pump) will have main alt and an SD-8 for backup. My question is around failure detection. It seems to me NOT to be a good idea to rely on voltage reduction to detect an alternator failure, because it may take a while for the volts to dip if at all. A much better way would appear to be to use the Dynon engine management system to measure current from the alternator and to set an alarm below the minimum day VFR loads...This alarm would send an audio tone thru my headset... This method should work fine if I only had one alternator...with the SD-8 I have 2 and the current may not drop that low because the min day VFR could be a s low as 7 to 8 amps, depending on voltage the Main alt may only be generating a couple of amps and a failure difficult to detect. An alternative would be not to run the SD-8 unless I had to...I.e keep it switched off...if the main alt dies or trips on OV I get a low current alarm...Then bang on the SD-8 and start load managing. Any flaw in the logic here?...Can I switch an SD-8 like this? Thanks Frank ________________________________ Message 28 ____________________________________ Time: 12:03:07 PM PST US From: Subject: AeroElectric-List: Re: Garmin 196 interferes with com radio --> AeroElectric-List message posted by: You might consider the power wire to the 196 is producing EMF or RF at that one freq. A power filter may help but suggest you may consider trying the below: I agree the stock cable is not shielded but the one suggested by Joe I don't think will work for the 196 (which does not have a round receptacle). You could take the stock harness and cut the wires off near the plug and splice in a shielded cable for the stock wires, or you could reroute the power cable away from coax or other wires to the radio. Before you do anything I wounder if you can borrow another 196 and plug it in to see if it is the unit itself. Sounds like a very specific freq. I was thinking it could be also picked up by the intercom but because it is on one freq it seems to me it is RF interference at that one freq. A shielded or rerouted cable might help? EMF or IF problems have been solved by just physically moving or separating the wires. A testimonial will not help but my 196 mounted in the panel above my KX155 never had any interference. You already confirmed that is is coming thru the power line. Good Luck George From: Cameron Kurth Subject: Garmin 196 interferes with com radio I have a Garmin 196 that is wired into the plane's power buss. I get interference at a small range of frequencies on my com radio from the Garmin (just happens to be Detroit approach). If I pull the fuse to the Garmin so it runs off the battery the interference goes away. It's a similar interference that the Dynon D10's had when they first came out. So, what kind of filter should I use? Will the Radio Shack 270-055 work in this situation? I called Garmin about it. They said that the 196 was a handheld so it has to meet the same specs as a toaster. They were very nice about it but quite clear that it's only a handheld so it was not designed for airplane use and I'm on my own. Thanks Cam ________________________________ Message 29 ____________________________________ Time: 12:08:46 PM PST US From: chad-c_sip@stanfordalumni.org Subject: Re: AeroElectric-List: Multimeter problem Z-USANET-MsgId: XID379JggTiP0479X38 --> AeroElectric-List message posted by: chad-c_sip@stanfordalumni.org Do you have a resistor lying around that you could use to do a current test? You'll probably want to solder the ends of the resistor to some wire so you have a nice solid contact. Then use your various multimeters to measure the current flow across the terminals. If all 3 multimeters think the resistance of the resistor is the same and they all measure the same current then you know the voltage of the battery: V = I * R Use a large-ish resistor and you won't drain your batteryat all in the process. 10 kOhms should be a nice small current to look at. And your multimeters shouldn't have any trouble with that. If the multimeters disagree on the resistance of the resistor or measure the currents differently then your meters aren't accurate enough for this measurement. If you've got an 8-bit A to D in those meters on a -20 to 20V range you're looking at 156 mV as the least significant bit. That's not going to be enough. I honestly don't know if those various multimeters are 8, 10, or 12 bit devices. Good luck. Chad Chad Sipperley Lancair IVP-turbine (under construction) Phoenix, AZ ------ Original Message ------ From: Paul Wilson Subject: AeroElectric-List: Multimeter problem > --> AeroElectric-List message posted by: Paul Wilson > > I have 3 digital multimeters that do not agree at all. Unfortunately I > posted some battery voltages on a large automotive AGM Optima battery that > are now highly suspect. > On the battery which was freshly charged: > 1) GB Instruments GDT-11 bought at Home Depot about 2 months ago > 12.80v, same with new 9v battery > 2) Radio Shack Auto ranging # 22-163, about 2 years old > 12.55v same with new AA cells > 3) Radio Shack # 22-191, 8-10 years old > 12.69v same with new AA cells. > > Way to much difference to tell the state of charge of this relatively new > battery. > How can I tell which units are reading correct voltages? Is there a test > I can perform? > > Thanks, Paul > > > > > > > ________________________________ Message 30 ____________________________________ Time: 12:42:04 PM PST US From: Mickey Coggins Subject: Re: AeroElectric-List: Re: Garmin 196 interferes with com radio --> AeroElectric-List message posted by: Mickey Coggins > I agree the stock cable is not shielded but the one suggested by Joe > I don't think will work for the 196 (which does not have a round > receptacle). My Garmin 196 has a round receptacle, just like the one Joe has. -- Mickey Coggins http://www.rv8.ch/ #82007 finishing do not archive ________________________________ Message 31 ____________________________________ Time: 12:47:08 PM PST US From: "Eric M. Jones" Subject: AeroElectric-List: Re: DC fans problem. --> AeroElectric-List message posted by: "Eric M. Jones" --> AeroElectric-List message posted by: Mickey Coggins > ... Make sure you put a Transient Voltage Suppressor across every DC fan > and every relay > and coil and motor unless an oscilloscope says you don't need to. >What would be the part number for that Transient Voltage Suppressor? >Do you sell them with a pretty picture like you have for the rest >of your stuff? Thanks, Mickey Mickey, Bidirectional transorb P6KE18CA will do the job and Digikey has them. I do sell these in a 12-pack as "SnapJacks" including shrink tubing and connector lugs and mysterious details sufficient to outfit a typical small airplane. Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 "Democracy is the theory that the common people know what they want and deserve to get it good and hard." -- H. L. Mencken ________________________________ Message 32 ____________________________________ Time: 01:25:51 PM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Regulator output --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 11:56 AM 7/7/2005 -0500, you wrote: >--> AeroElectric-List message posted by: Charlie Brame > >Bob, et. al., > >The electrical system in my RV-6A is configured very close to Bob's >Z-13, All Electric on a Budget. I have a B&C alternator and a Ford >equivalent regulator which is adjustable and bench set to 13.8 volts. >With the main contactor off and using the essential bus only, I show >about 13.5 volts at the bus. However, when using the normal system with >the essential bus powered through a diode, the essential bus only shows >12.8 volts. This is understandable considering the loss through the >contactor and the diode. > >My avionics and my gyros (ADI and DG) are connected via the essential >bus and I wonder if a higher voltage would improve both radio and gyro >perfomance somewhat. > >My question is: should I up the regulator voltage in order to get close >to 13.8 volts at the essential bus when using the main or normal system? >This would result in 14+ volts on the main bus, but that shouldn't >adversely affect anything, IMHO. No. When the alternator is running, it's set for 13.8 plus which puts 13.0 plus on the e-bus. When when the alternator stops, you move the e-bus feed directly to the battery which delivers it's capacity over the range of 12.5 down to about 11.0 volts. Assuming you've chosen instruments that are designed to operate over the range of battery supply voltages, then I'll suggest that an alternator-ON operating voltage of 13.0 to 13.8 is superior to the still satisfactory alternator-OFF operating voltage of 11.0 to 12.5. The diode drop is, therefore insignificant. Further, the energy dissipation differences between the various technologies are also insignificant while the alternator is operating because you have a 500+ watt, unlimited duration energy source supplying all the BTUs. When you're down to battery-only ops, then energy expenditure needs to be considered more closely . . . This is why you seldom see a diode of any kind downstream of a battery feed in my drawings. Bob . . . ________________________________ Message 33 ____________________________________ Time: 01:46:19 PM PST US From: Cameron Kurth Subject: Re: AeroElectric-List: Re: Garmin 196 interferes with com radio --> AeroElectric-List message posted by: Cameron Kurth Looks like shielding the wires is my best first try. > > A testimonial will not help but my 196 mounted in > the panel above my KX155 never had any interference. > You already confirmed that is is coming thru the > power line. It took me almost 130 hours of flying to find the problem. It's only one frequency and it's only when I'm quite a distance away from the source. When I'm close to Detroit there is no problem. I have to be at least 30 miles out before the interefence becomes a problem. I assume that the interfernce is quite minor so a small improvement is all I may need. Thanks for the input. Cam ________________________________ Message 34 ____________________________________ Time: 02:21:36 PM PST US From: "Eric M. Jones" Subject: AeroElectric-List: Re: Multimeter problem --> AeroElectric-List message posted by: "Eric M. Jones" Paul, Proper ventillation when doing fiberglass work is essential to avoid becoming distracted on small problems like this. Let's say the average of the three meters is 12.68 volts. Then the worst case is that the meters have an error of: GB Instruments GDT-11 12.80v........................+0.95%.......Under 1% error. Very good Radio Shack Auto ranging # 22-163 12.55v....... -1.03%.......Over 1% error. Obviously Radio Shack junk Radio Shack # 22-191 12.69v..........................+0.08%........Under 1/10 %. Well...even a blind pig finds an acorn sometimes. Now, measuring battery voltages separately with meters is fraught with error because of the small differences in meter impedance. To get numbers that are meaningful you need to measure the same battery at the same time with all the meters simultaneously. Final word: Build the airplane....... Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge MA 01550-2705 (508) 764-2072 "Everything you've learned in school as "obvious" becomes less and less obvious as you begin to study the universe. For example, there are no solids in the universe. There's not even a suggestion of a solid. There are no absolute con- tinuums. There are no surfaces. There are no straight lines." - R. Buckminster Fuller ------ Original Message ------ From: Paul Wilson Subject: Multimeter problem > --> AeroElectric-List message posted by: Paul Wilson > > I have 3 digital multimeters that do not agree at all. Unfortunately I > posted some battery voltages on a large automotive AGM Optima battery that > are now highly suspect. > On the battery which was freshly charged: > 1) GB Instruments GDT-11 bought at Home Depot about 2 months ago > 12.80v, same with new 9v battery > 2) Radio Shack Auto ranging # 22-163, about 2 years old > 12.55v same with new AA cells > 3) Radio Shack # 22-191, 8-10 years old > 12.69v same with new AA cells. > > Way to much difference to tell the state of charge of this relatively > new > battery. > How can I tell which units are reading correct voltages? Is there a test > I can perform? > > Thanks, Paul ________________________________ Message 35 ____________________________________ Time: 02:43:22 PM PST US From: Dave Morris Subject: Re: AeroElectric-List: Multimeter problem --> AeroElectric-List message posted by: Dave Morris Stick a 7812 voltage regulator on it, and see what the 3 meters read. The one that reads 12.0V is the winner. Dave Morris At 12:05 PM 7/7/2005, you wrote: >--> AeroElectric-List message posted by: Paul Wilson > >I have 3 digital multimeters that do not agree at all. Unfortunately I >posted some battery voltages on a large automotive AGM Optima battery that >are now highly suspect. > On the battery which was freshly charged: >1) GB Instruments GDT-11 bought at Home Depot about 2 months ago >12.80v, same with new 9v battery >2) Radio Shack Auto ranging # 22-163, about 2 years old >12.55v same with new AA cells >3) Radio Shack # 22-191, 8-10 years old >12.69v same with new AA cells. > > Way to much difference to tell the state of charge of this relatively new >battery. > How can I tell which units are reading correct voltages? Is there a test >I can perform? > >Thanks, Paul > > ________________________________ Message 36 ____________________________________ Time: 03:21:57 PM PST US From: "Robert L. Nuckolls, III" Subject: RE: AeroElectric-List: DC fans problem. --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" > >A customer of mine bought a solid state relay from me but it failed when >driving a small DC fan. This certainly does not speak well of the >ruggedness of the solid state device. It is based on the International >Rectifier IPS5551T with a few added features and additional EMI >protection. I test these things at 60 Amps. > >Examining the SSR didn't help much except to show that the chip was toast >and that it probably didn't fail from current (usually current failures >show cracked cases). Besides the thing has overcurrent and overtemp >protection. This was a mystery that took far too long to solve...but >finally I checked the whole circuit and found that when a DC fan is turned >off, it becomes a power generator for at least a few seconds, and the >voltage output (no load!) can easily exceed the specs of the SSR. I went to the bench and ran some brushless fans. One was a 1.8W, 12V motor, the other was an 8W, 12V device. I was curious as to the form and energy content of any transients I could see. Using the "Nuckolls, super-fast, arc-less test switch" I was able to capture some 60v, positive going transients on the little 1.8W motor. These were about 1 sec wide at the base, 60V tall and dropped to 40V when loaded with 1K. This suggests the source impedance of the spike generator is about 500 ohms since 2/3 of the spike would remain across the 1K load. Since we're working back to a 15 volt (round numbers) bus, we could extrapolate 45 volts being available to "spike" the solid state relay with a current delivery (60-15)/500 = .09 amps. This translates to an energy content for each spike of about 45(volts) x 1.0(assume area under curve is square . . . which it cannot be) x .09(amps) x 1(uSec) or about 27 microJoules per spike. I always got 4 in a row for each fan disconnect (4-pole motor?) for a total energy dump of 108 microJoules. FETs have an inherent 'body diode' that will go into conduction if you try to carry the source more positive than the drain. So in this case, all the energy feeding back from the motor gets sinked off to the bus and resultant reverse stress on the FET is under 1 volt. The specs for handling inductive load energy dumps for the switch (See http://www.irf.com/product-info/datasheets/data/ips5551t.pdf Figures 10 and 19) cites inductive load handling abilities fare in excess of the 100+ microJoules calculated above by several orders of magnitude. Are you sure the mechanism by which the switch failed has been properly illuminated? I'm having trouble believing these itty-bitty spikes are hazardous to a IPS5551 high side switch. I noted further that these spikes could not have been related to a counter-emf spin-down. The observable CEMF output dropped to 50% applied voltage at switch opening and took about 3 seconds to drop to 5% of applied voltage. Bob . . . ________________________________ Message 37 ____________________________________ Time: 03:56:50 PM PST US From: Paul Wilson Subject: Re: AeroElectric-List: Re: Multimeter problem --> AeroElectric-List message posted by: Paul Wilson Thanks Eric, I had been using the bad meter and was trying to figure why the batt always read low suspected it needed charging. Yes it was a distraction. I am off this issue and will find a better meter to use in the shop and call the question resolved. The GB meter is one I leave at home for messing with AA powered gadgets. It only cost around $10 compared to the RS ones which were much more expensive. BTW I did try Chad's suggestion and the numbers were all over the place because the meters wont read amps that are accurate enough. Hey guys, suggest a cost effective meter that I can rely on. Thanks, Paul ===================== At 03:20 PM 7/7/2005, you wrote: >--> AeroElectric-List message posted by: "Eric M. Jones" > >Paul, > >Proper ventillation when doing fiberglass work is essential to avoid >becoming distracted on small problems like this. > >Let's say the average of the three meters is 12.68 volts. Then the worst >case is that the meters have an error of: > > GB Instruments GDT-11 12.80v........................+0.95%.......Under 1% >error. Very good > Radio Shack Auto ranging # 22-163 12.55v....... -1.03%.......Over 1% error. >Obviously Radio Shack junk > Radio Shack # 22-191 12.69v..........................+0.08%........Under >1/10 %. Well...even a blind pig finds an acorn sometimes. > >Now, measuring battery voltages separately with meters is fraught with error >because of the small differences in meter impedance. To get numbers that are >meaningful you need to measure the same battery at the same time with all >the meters simultaneously. > >Final word: Build the airplane....... > >Eric M. Jones >www.PerihelionDesign.com >113 Brentwood Drive >Southbridge MA 01550-2705 >(508) 764-2072 > >"Everything you've learned in school as "obvious" becomes >less and less obvious as you begin to study the universe. >For example, there are no solids in the universe. There's >not even a suggestion of a solid. There are no absolute con- >tinuums. There are no surfaces. There are no straight lines." > > - R. Buckminster Fuller > >------ Original Message ------ >From: Paul Wilson >To: aeroelectric-list@matronics.com >Subject: Multimeter problem > > > --> AeroElectric-List message posted by: Paul Wilson > > > > I have 3 digital multimeters that do not agree at all. Unfortunately I > > posted some battery voltages on a large automotive AGM Optima battery that > > are now highly suspect. > > On the battery which was freshly charged: > > 1) GB Instruments GDT-11 bought at Home Depot about 2 months ago > > 12.80v, same with new 9v battery > > 2) Radio Shack Auto ranging # 22-163, about 2 years old > > 12.55v same with new AA cells > > 3) Radio Shack # 22-191, 8-10 years old > > 12.69v same with new AA cells. > > > > Way to much difference to tell the state of charge of this relatively > > new > > > battery. > > How can I tell which units are reading correct voltages? Is there a test > > I can perform? > > > > Thanks, Paul > > ________________________________ Message 38 ____________________________________ Time: 04:50:52 PM PST US From: chad-c_sip@stanfordalumni.org Subject: Re: AeroElectric-List: Re: Multimeter problem Z-USANET-MsgId: XID494JggXvP0235X30 --> AeroElectric-List message posted by: chad-c_sip@stanfordalumni.org I don't know about cost-effective in the short run. But in the lab for my graduate work we only used Flukes. All the other el-cheapo meters died within a year and were totally unreliable for anything critical. I've had the same Fluke multimeter for about 6 years now going on it's 10th or more set of batteries and third set of probes. Chad Chad Sipperley Lancair IVP-turbine (under construction) Phoenix, AZ ------ Original Message ------ From: Paul Wilson Subject: Re: AeroElectric-List: Re: Multimeter problem > --> AeroElectric-List message posted by: Paul Wilson > > Thanks Eric, > I had been using the bad meter and was trying to figure why the batt > always read low suspected it needed charging. Yes it was a distraction. I > am off this issue and will find a better meter to use in the shop and call > the question resolved. The GB meter is one I leave at home for messing with > AA powered gadgets. It only cost around $10 compared to the RS ones which > were much more expensive. > BTW I did try Chad's suggestion and the numbers were all over the place > because the meters wont read amps that are accurate enough. > > Hey guys, suggest a cost effective meter that I can rely on. > > Thanks, Paul > ===================== > > At 03:20 PM 7/7/2005, you wrote: > >--> AeroElectric-List message posted by: "Eric M. Jones" > > > >Paul, > > > >Proper ventillation when doing fiberglass work is essential to avoid > >becoming distracted on small problems like this. > > > >Let's say the average of the three meters is 12.68 volts. Then the worst > >case is that the meters have an error of: > > > > GB Instruments GDT-11 12.80v........................+0.95%.......Under 1% > >error. Very good > > Radio Shack Auto ranging # 22-163 12.55v....... -1.03%.......Over 1% error. > >Obviously Radio Shack junk > > Radio Shack # 22-191 12.69v..........................+0.08%........Under > >1/10 %. Well...even a blind pig finds an acorn sometimes. > > > >Now, measuring battery voltages separately with meters is fraught with error > >because of the small differences in meter impedance. To get numbers that are > >meaningful you need to measure the same battery at the same time with all > >the meters simultaneously. > > > >Final word: Build the airplane....... > > > >Eric M. Jones > >www.PerihelionDesign.com > >113 Brentwood Drive > >Southbridge MA 01550-2705 > >(508) 764-2072 > > > >"Everything you've learned in school as "obvious" becomes > >less and less obvious as you begin to study the universe. > >For example, there are no solids in the universe. There's > >not even a suggestion of a solid. There are no absolute con- > >tinuums. There are no surfaces. There are no straight lines." > > > > - R. Buckminster Fuller > > > >------ Original Message ------ > >From: Paul Wilson > >To: aeroelectric-list@matronics.com > >Subject: Multimeter problem > > > > > --> AeroElectric-List message posted by: Paul Wilson > > > > > > I have 3 digital multimeters that do not agree at all. Unfortunately I > > > posted some battery voltages on a large automotive AGM Optima battery that > > > are now highly suspect. > > > On the battery which was freshly charged: > > > 1) GB Instruments GDT-11 bought at Home Depot about 2 months ago > > > 12.80v, same with new 9v battery > > > 2) Radio Shack Auto ranging # 22-163, about 2 years old > > > 12.55v same with new AA cells > > > 3) Radio Shack # 22-191, 8-10 years old > > > 12.69v same with new AA cells. > > > > > > Way to much difference to tell the state of charge of this relatively > > > new > > > > > battery. > > > How can I tell which units are reading correct voltages? Is there a test > > > I can perform? > > > > > > Thanks, Paul > > > > > > > > > > > ________________________________ Message 39 ____________________________________ Time: 05:29:45 PM PST US From: Joemotis@aol.com Subject: Re: AeroElectric-List: Re: Multimeter problem --> AeroElectric-List message posted by: Joemotis@aol.com Fluke 87 period. I am a Union special skills electrician and would not trust my LIFE to anything else. Owned Flukes for 20 years and it was the venerable Simpson 260 before that. Joe Do not archive ________________________________ Message 40 ____________________________________ Time: 05:59:32 PM PST US From: Charlie England Subject: Re: AeroElectric-List: ICOM PTT --> AeroElectric-List message posted by: Charlie England bakerocb@cox.net wrote: >--> AeroElectric-List message posted by: > >AeroElectric-List message previously posted by: Charlie England >ceengland@bellsouth.net > > > > >>AeroElectric-List message posted by: bakerocb@cox.net >> >> > > > >>.....skip.......My question is: Can I instead use my standard push-to-talk >>switch, with the >>larger diameter sized microphone receptacle and plug such as David Clark >>and >>Telex sell, in line with the microphone plug from the headset to the >>OPC-752 >>Adapter to key the IC-A4 transmitter?......skip >> >> > > >Plug in the headset adaptor, turn on the radio & push the side mounted >xmit button. Does the xmit led light up? My IC-A4 works fine using the >adaptor & the regular xmit button. My manual says the radio won't work while >on the external charge jack >(exactly opposite what the ICOM rep promised me before I bought it). Charlie > >7/7/2005 > >Hello Charlie, Thanks for your input and suggestion -- I will try that. But >lighting up a light is no absolute guarantee that you are transmitting a >signal. Only using a separate receiver and receiving a signal would >guarantee that -- I am a skeptical type. > >I agree that there are some misleading / incorrect statements in the manual, >but I think some caution is in order in interpreting or rejecting them. > >Here are two extracts from my manual: > >"EXTERNAL DC POWER JACK [CHARGE]Connect a 12 to 16 V DC power source using >the optional >cables, CP-12L or OPC-254L, to charge the attached battery pack; or connect >the BC-110V wall charger for charging. CAUTION:This connection is for >charging ONLY. Power to the transceiver must be turned OFF during charging." >..... "CP-12L CIGARETTE LIGHTER CABLE WITH NOISE FILTER >Allows you to charge a battery pack connected to the transceiver via a DC >power source (12-16 V DC) For charging ONLY-the transceiver cannot be >simultaneously operated." > >I was researching something on the IC-A4 earlier and was told by some >authoritative source (can't recall who now) that: Yes, the radio would work >when you are providing DC power to the external DC power jack, but the radio >is designed to operate on 9.6 volts DC -- the output from a normal battery >pack. If instead you try to operate the radio when some higher DC voltage is >being applied to the external DC power jack you run the risk of damaging the >radio. > >No specific information on just how high that higher DC voltage has to be >coming into the external DC power jack in order to damage the radio while >attemping to operate it, but caution would be in order. > >OC > My reply was rather poorly worded. I should have said that mine actually works fine in both xmit & rcv using the headset adaptor & the builtin PTT. I assumed that you had no 2nd radio to test with, & the led is a pretty strong indicator that the button is doing what it claims to do. Consider the extra design/circuit work involved in making it light under both conditions of transmit & no-transmit. from another post: >>>I did try something similar by attempting to transmit with my IC-A4 to my Sporty's Air Scan V radio, but only generated a squeal. I assumed that I was too close and over powering the Sporty's radio receiver. This left me still uncertain of my IC-A4's capability in regard to using a standard push to talk button. >>> Repeat the test with the scanner in an adjacent room or walk outside & let someone else listen to the scanner. Odds are, the squeal was actually feedback caused by the mic on the ICOM picking up its own audio from the scanner, amplifying, retransmitting, etc. RE:operation while charging issues, if the radio would be damaged by external charge voltage due to operating on 9.6 V, the battery would also be damaged rather quickly from the same overvoltage. It is so simple to design this feature into the radio that it never occurred to me to question the rep's word about it. I was shocked & disgusted when I discovered that he lied about it & that I couldn't use ship's power, even with a purpose built adapter, to both keep the battery topped off & operate the radio. (Ahh well... rants about ICOM's ?integrity? are best left for another post.) Good luck with your testing, Charlie ________________________________ Message 41 ____________________________________ Time: 05:59:32 PM PST US From: "Robert L. Nuckolls, III" Subject: AeroElectric-List: Alternator output --> AeroElectric-List message posted by: "Robert L. Nuckolls, III" At 10:53 AM 7/7/2005 -0700, you wrote: So my all electric IFR plane (no mech fuel pump) will have main alt and an SD-8 for backup. My question is around failure detection. It seems to me NOT to be a good idea to rely on voltage reduction to detect an alternator failure, because it may take a while for the volts to dip if at all. Absolutely not true. Batteries charge, and alternators are set down. A low voltage light set for 13.0 volts comes on in seconds after the alternator quits. A much better way would appear to be to use the Dynon engine management system to measure current from the alternator and to set an alarm below the minimum day VFR loads...This alarm would send an audio tone thru my headset... This method should work fine if I only had one alternator...with the SD-8 I have 2 and the current may not drop that low because the min day VFR could be a s low as 7 to 8 amps, depending on voltage the Main alt may only be generating a couple of amps and a failure difficult to detect. An alternative would be not to run the SD-8 unless I had to...I.e keep it switched off...if the main alt dies or trips on OV I get a low current alarm...Then bang on the SD-8 and start load managing. That's the recommended operating procedure. SD-8 stays off until after you get a low-volts light to show that main alternator is off. Then turn SD-8 ON, Main battery master OFF. Continue in en route endurance mode until airport in sight. Close battery master contactor to bring main bus up to use any equipment you like for approach to landing. Bob . . . ________________________________ Message 42 ____________________________________ Time: 06:31:29 PM PST US From: Ken Subject: Re: AeroElectric-List: ICOM PTT --> AeroElectric-List message posted by: Ken snip >RE:operation while charging issues, if the radio would be damaged by external charge voltage due to operating on 9.6 V, the battery would also be damaged rather quickly from the same overvoltage. It is so simple to design this feature into the radio that it never occurred to me to question the rep's word about it. I was shocked & disgusted when I discovered that he lied about it & that I couldn't use ship's power, even with a purpose built adapter, to both keep the battery topped off & operate the radio. (Ahh well... rants about ICOM's ?integrity? are best left for another post.) > >Good luck with your testing, > >Charlie > > Do we know that it won't transmit reliably while charging or that damage occurs? I certainly listen to my A4 while it is charging. I don't think I've transmitted for more than a few seconds while charging though. The marketing types who write icom manuals can't or don't talk to the engineers IMO. I suspect the engineers wouldn't let it turn on while charging if damage was likely. The rep may know more than the manual... Ken ________________________________ Message 43 ____________________________________ Time: 07:03:25 PM PST US From: "John D. Heath" Subject: Re: AeroElectric-List: Re: Multimeter problem --> AeroElectric-List message posted by: "John D. Heath" ----- Original Message ----- From: "John D. Heath" Subject: Re: AeroElectric-List: Re: Multimeter problem > I have a Fluke 88 DMM I bought when they first came out, about 1985 I > think. It was in use daily until I retired in 2000. I sent it in for free > calibration every 2 years and it never let me down. The only thing I don't > like about it is, when it gets knocked of a fender and you catch it by the > leads, the little insulators where the leads plug in, suffer and sooner or > later give it up. Want to do good work? Buy good tools. > > John D. Heath > > DO NOT ARCHIVE > > ----- Original Message ----- > From: > To: > Sent: Thursday, July 07, 2005 7:25 PM > Subject: Re: AeroElectric-List: Re: Multimeter problem > > >> --> AeroElectric-List message posted by: Joemotis@aol.com >> >> Fluke 87 period. I am a Union special skills electrician and would not >> trust >> my LIFE to anything else. >> Owned Flukes for 20 years and it was the venerable Simpson 260 before >> that. >> >> Joe >> Do not archive >> >> >> >> >> >> >