---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Sat 09/23/17: 8 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 04:11 PM - Voltmeter & Ammeter normal ranges (Sebastien) 2. 04:47 PM - Re: Voltmeter & Ammeter normal ranges (user9253) 3. 05:13 PM - Re: Voltmeter & Ammeter normal ranges (Charlie England) 4. 05:59 PM - Unsupported coax length (Paul Eckenroth) 5. 07:01 PM - Re: Re: Voltmeter & Ammeter normal ranges (Sebastien) 6. 07:17 PM - Re: Voltmeter & Ammeter normal ranges (user9253) 7. 07:52 PM - Re: Voltmeter & Ammeter normal ranges (ashleysc@broadstripe.net) 8. 09:25 PM - Re: Voltmeter & Ammeter normal ranges (Sebastien) ________________________________ Message 1 _____________________________________ Time: 04:11:43 PM PST US From: Sebastien Subject: AeroElectric-List: Voltmeter & Ammeter normal ranges I am doing the test flying on a friend's RV-6 and as part of the preparation I set up the engine monitor (Dynon 120) to display the following on the voltmeter and ammater: Voltmeter: Red below 10V, Yellow 10-13.8V, Green 13.8V-14.5V, Red > 14.5V Ammeter (wired to show current flow in to the batter): Red < 0A, Green 0 - 5A, Yellow 5-30A, Red > 30A. Battery is an Odyssey PC680 AGM. Alternator and regulator unknown, came with the kit from Van's 10-20 years ago. My guess is Plane Power. First Question: Do the ammeter settings seem reasonable? Obviously any discharge (<0A) is red as indicative of a problem that requires landing ASAP. Normal charge after a start has been observed to be < 5A within a minute after start, a hard start or low battery would obviously make this worse so I set green as 0-5A but don't have any good basis for this. Same for the yellow and red bands. I want the yellow band to indicate that a long time in this area is a problem, and red to be an immediate problem. Normally once the battery has been charged after a start the value should be zero so perhaps the green band should be 0-1A? What charge level going into this battery would indicate an immediate problem (red band)? \ After first flight the low current alarm was constantly going off so I changed it from <0 to <1. Second flight had similar but not as frequent problem so I was going to lower it a little more but then I was able to download the engine monitor data to Savvy and WOW is it fantastic being able to look at graphs of engine data. I have no idea what normal would look like but here is a snap shot of the second flight: You can see the battery amps wander between -2 to +2, with excursions to -3 +3 later in the flight (during large engine power changes). Second Question: Is this behaviour indicative of: A. Normal operation B. Sensor problem C. Charging system or battery problem D. Something else Thank you all for your input. ________________________________ Message 2 _____________________________________ Time: 04:47:55 PM PST US Subject: AeroElectric-List: Re: Voltmeter & Ammeter normal ranges From: "user9253" My D-180 ammeter varies up and down to unreasonable numbers. I disconnected the shunt and put a jumper directly across the plus and minus input on the D-180. One would expect the D-180 to display 0 amps. But no, it still varies up and down, not as bad as before, but still plus and minus 15 or 20 amps. I believe it is a software problem. Maybe the Dynon 120 has the same problem. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=473105#473105 ________________________________ Message 3 _____________________________________ Time: 05:13:21 PM PST US Subject: Re: AeroElectric-List: Voltmeter & Ammeter normal ranges From: Charlie England On 9/23/2017 6:09 PM, Sebastien wrote: > I am doing the test flying on a friend's RV-6 and as part of the > preparation I set up the engine monitor (Dynon 120) to display the > following on the voltmeter and ammater: > > Voltmeter: Red below 10V, Yellow 10-13.8V, Green 13.8V-14.5V, Red > 14.5V > Ammeter (wired to show current flow in to the batter): Red < 0A, Green > 0 - 5A, Yellow 5-30A, Red > 30A. > > Battery is an Odyssey PC680 AGM. Alternator and regulator unknown, > came with the kit from Van's 10-20 years ago. My guess is Plane Power. > > First Question: Do the ammeter settings seem reasonable? Obviously any > discharge (<0A) is red as indicative of a problem that requires > landing ASAP. Normal charge after a start has been observed to be < 5A > within a minute after start, a hard start or low battery would > obviously make this worse so I set green as 0-5A but don't have any > good basis for this. Same for the yellow and red bands. I want the > yellow band to indicate that a long time in this area is a problem, > and red to be an immediate problem. Normally once the battery has been > charged after a start the value should be zero so perhaps the green > band should be 0-1A? What charge level going into this battery would > indicate an immediate problem (red band)? > \ > After first flight the low current alarm was constantly going off so I > changed it from <0 to <1. Second flight had similar but not as > frequent problem so I was going to lower it a little more but then I > was able to download the engine monitor data to Savvy and WOW is it > fantastic being able to look at graphs of engine data. I have no idea > what normal would look like but here is a snap shot of the second flight: > > You can see the battery amps wander between -2 to +2, with excursions > to -3 +3 later in the flight (during large engine power changes). > > Second Question: Is this behaviour indicative of: > > A. Normal operation > B. Sensor problem > C. Charging system or battery problem > D. Something else > > Thank you all for your input. Well, here's my 2 volts... Current readings depend on where the sensor is located in the system. Assuming it's between the battery lead & the bus, it will show charge for at least a short time after engine start, to replenish the battery. After that, it should show more or less zero (with some slight variation) because the alternator has fully charged the battery (no more electrons flowing into the battery) and is supplying all the electron needs of the avionics, etc. It would show discharge whenever the alternator couldn't keep up with the load demands of the a/c, and the battery started picking up the balance of the demand. (Shouldn't happen unless you've intentionally undersized the alternator to save weight, and are willing to accept temporary discharge during very short term events like landing lights, gear extension/retraction, etc.) Other time you'd see it is if the charging system is failing or has failed. But I don't even have an ammeter on my current plane, & don't plan to install one in the plane I'm building. Alternator voltage gives all info needed during flight. Voltage: At 10 volts, the battery is effectively dead, and you might not see *any* indication from the EFIS engine monitor (or from the EFIS itself). If I were setting limits, I'd realize that anything under around 12.5 volts means the charging system is effectively dead (red). I'd probably set the red limit even higher; around 13.5, because I'd want to know instantly that I've lost charging. I'd only see the yellow band as useful to show intermittent excess demand situations, where it would go in & out of yellow as really big loads were exceeding the alternator's capacity. So yellow from around 13.5 to just under that particular alternator's 'normal' output voltage, which hopefully, is over 14.3 or so to keep the AGM battery fully charged. Red again above about 14.8 or so, since Odyssey says 14.7 is a safe level of initial charge voltage. Hope its at least worth what you paid... Charlie --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 4 _____________________________________ Time: 05:59:46 PM PST US From: Paul Eckenroth Subject: AeroElectric-List: Unsupported coax length Looking for advise on what the max acceptable unsupported horizontal length of RG400 coax might be. I have 23" between fuselage ribs and was planning on running the coax through a grommet in the tooling holes but then started questioning if this was good practice. So opinions are requested. Thanks Paul ________________________________ Message 5 _____________________________________ Time: 07:01:51 PM PST US From: Sebastien Subject: Re: AeroElectric-List: Re: Voltmeter & Ammeter normal ranges Very interesting Joe, thanks for the reply. Did you try upgrading the firmware? Did you follow up with Dynon about this behaviour? In view of your experience I think I'll give them a call on Monday. Sebastien > On Sep 24, 2017, at 01:47, user9253 wrote: > > > My D-180 ammeter varies up and down to unreasonable numbers. I disconnected the shunt and put a jumper directly across the plus and minus input on the D-180. One would expect the D-180 to display 0 amps. But no, it still varies up and down, not as bad as before, but still plus and minus 15 or 20 amps. I believe it is a software problem. Maybe the Dynon 120 has the same problem. > > -------- > Joe Gores > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=473105#473105 > > > > > > > > > ________________________________ Message 6 _____________________________________ Time: 07:17:21 PM PST US Subject: AeroElectric-List: Re: Voltmeter & Ammeter normal ranges From: "user9253" Yes, the D-180 firmware is up to date. No, I did not contact Dynon. The ammeter function is not important to me. I agree with Charlie, the voltmeter tells me how the charging system is working. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=473109#473109 ________________________________ Message 7 _____________________________________ Time: 07:52:11 PM PST US From: ashleysc@broadstripe.net Subject: Re: AeroElectric-List: Voltmeter & Ammeter normal ranges Hi Sebastien; Flow out of the battery is not abnormal and will happen whenever your aircraft consumes more power than its alternator can generate. It is not generally a signal to land immediately, but to reduce power consumption (like turn off the landing lights). Cheers! Stu. ----- Original Message ----- From: "Sebastien" Sent: Saturday, September 23, 2017 4:09:48 PM Subject: AeroElectric-List: Voltmeter & Ammeter normal ranges I am doing the test flying on a friend's RV-6 and as part of the preparation I set up the engine monitor (Dynon 120) to display the following on the voltmeter and ammater: Voltmeter: Red below 10V, Yellow 10-13.8V, Green 13.8V-14.5V, Red > 14.5V Ammeter (wired to show current flow in to the batter): Red < 0A, Green 0 - 5A, Yellow 5-30A, Red > 30A. Battery is an Odyssey PC680 AGM. Alternator and regulator unknown, came with the kit from Van's 10-20 years ago. My guess is Plane Power. First Question: Do the ammeter settings seem reasonable? Obviously any discharge (<0A) is red as indicative of a problem that requires landing ASAP. Normal charge after a start has been observed to be < 5A within a minute after start, a hard start or low battery would obviously make this worse so I set green as 0-5A but don't have any good basis for this. Same for the yellow and red bands. I want the yellow band to indicate that a long time in this area is a problem, and red to be an immediate problem. Normally once the battery has been charged after a start the value should be zero so perhaps the green band should be 0-1A? What charge level going into this battery would indicate an immediate problem (red band)? \ After first flight the low current alarm was constantly going off so I changed it from <0 to <1. Second flight had similar but not as frequent problem so I was going to lower it a little more but then I was able to download the engine monitor data to Savvy and WOW is it fantastic being able to look at graphs of engine data. I have no idea what normal would look like but here is a snap shot of the second flight: You can see the battery amps wander between -2 to +2, with excursions to -3 +3 later in the flight (during large engine power changes). Second Question: Is this behaviour indicative of: A. Normal operation B. Sensor problem C. Charging system or battery problem D. Something else Thank you all for your input. ________________________________ Message 8 _____________________________________ Time: 09:25:11 PM PST US From: Sebastien Subject: Re: AeroElectric-List: Voltmeter & Ammeter normal ranges I'm guessing from some of the responses I'm getting that the picture I attac hed did not go through. The apparent current flow out of the battery is not f rom a high load. We're talking a 40-60 amp alternator powering 10 amps worth of instruments and radios. The load cycles from -2 to +2 amps at least 50 t imes over the course of a 1 hour flight and it's not because someone's hidin g under the floorboards flicking the lights on and off :). I'll try attaching the engine analyzer data again tomorrow. I did manage to c heck a few minutes of data from an identical analyzer in a different aircraf t and while it did cycle up and down a bit, it never showed negative. Sebastien > On Sep 24, 2017, at 04:50, ashleysc@broadstripe.net wrote: > > Hi Sebastien; > Flow out of the battery is not abnormal and will happen whenever your airc raft consumes more power than its alternator can generate. It is not general ly a signal to land immediately, but to reduce power consumption (like turn o ff the landing lights). > Cheers! Stu. > > From: "Sebastien" > To: aeroelectric-list@matronics.com > Sent: Saturday, September 23, 2017 4:09:48 PM > Subject: AeroElectric-List: Voltmeter & Ammeter normal ranges > > I am doing the test flying on a friend's RV-6 and as part of the preparati on I set up the engine monitor (Dynon 120) to display the following on the v oltmeter and ammater: > > Voltmeter: Red below 10V, Yellow 10-13.8V, Green 13.8V-14.5V, Red > 14.5V > Ammeter (wired to show current flow in to the batter): Red < 0A, Green 0 - 5A, Yellow 5-30A, Red > 30A. > > Battery is an Odyssey PC680 AGM. Alternator and regulator unknown, came wi th the kit from Van's 10-20 years ago. My guess is Plane Power. > > First Question: Do the ammeter settings seem reasonable? Obviously any dis charge (<0A) is red as indicative of a problem that requires landing ASAP. N ormal charge after a start has been observed to be < 5A within a minute afte r start, a hard start or low battery would obviously make this worse so I se t green as 0-5A but don't have any good basis for this. Same for the yellow a nd red bands. I want the yellow band to indicate that a long time in this ar ea is a problem, and red to be an immediate problem. Normally once the batte ry has been charged after a start the value should be zero so perhaps the gr een band should be 0-1A? What charge level going into this battery would ind icate an immediate problem (red band)? > \ > After first flight the low current alarm was constantly going off so I cha nged it from <0 to <1. Second flight had similar but not as frequent problem so I was going to lower it a little more but then I was able to download th e engine monitor data to Savvy and WOW is it fantastic being able to look at graphs of engine data. I have no idea what normal would look like but here i s a snap shot of the second flight: > > You can see the battery amps wander between -2 to +2, with excursions to - 3 +3 later in the flight (during large engine power changes). > > Second Question: Is this behaviour indicative of: > > A. Normal operation > B. Sensor problem > C. Charging system or battery problem > D. Something else > > Thank you all for your input. > ------------------------------------------------------------------------------------- Other Matronics Email List Services ------------------------------------------------------------------------------------- Post A New Message aeroelectric-list@matronics.com UN/SUBSCRIBE http://www.matronics.com/subscription List FAQ http://www.matronics.com/FAQ/AeroElectric-List.htm Web Forum Interface To Lists http://forums.matronics.com Matronics List Wiki http://wiki.matronics.com Full Archive Search Engine http://www.matronics.com/search 7-Day List Browse http://www.matronics.com/browse/aeroelectric-list Browse Digests http://www.matronics.com/digest/aeroelectric-list Browse Other Lists http://www.matronics.com/browse Live Online Chat! http://www.matronics.com/chat Archive Downloading http://www.matronics.com/archives Photo Share http://www.matronics.com/photoshare Other Email Lists http://www.matronics.com/emaillists Contributions http://www.matronics.com/contribution ------------------------------------------------------------------------------------- These Email List Services are sponsored solely by Matronics and through the generous Contributions of its members.