AeroElectric-List Digest Archive

Sun 06/08/14


Total Messages Posted: 8



Today's Message Index:
----------------------
 
     1. 04:52 AM - Re: Vans EGT gauge not working... (racerjerry)
     2. 08:05 AM - Re: Re: Vans EGT gauge not working... (R&J. Curtis)
     3. 09:44 AM - Re: Tyco W31 switch / breaker (Eric M. Jones)
     4. 09:53 AM - Re: Re: Vans EGT gauge not working... (Robert L. Nuckolls, III)
     5. 06:06 PM - Re: Re: Tyco W31 switch / breaker (Dj Merrill)
     6. 08:37 PM - Re: Tyco W31 switch / breaker (Vern Little)
     7. 09:40 PM - Fuse holders (Alan Barnett)
     8. 09:52 PM - Re: COZY: Fuse holders (Tim Andres)
 
 
 


Message 1


  • INDEX
  • Back to Main INDEX
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 04:52:19 AM PST US
    Subject: Re: Vans EGT gauge not working...
    From: "racerjerry" <gki@suffolk.lib.ny.us>
    > 1) Verified power and ground to the gauge. > As far as I know, power to simple analog EGT/CHT indicating systems are for internal lighting only. First of all, its much easier to test the EGT system by removing the sender from the exhaust system and heating the tip with a propane torch to see if you get needle movement need another person in the cockpit to watch gauge. Please use some precautions here so as to not burn your airplane nor anyone elses down. A fire extinguisher AND a handy 5 gal bucket of water along with common sense can work wonders. If that didnt work, the next thing to do is reverse the wires and recheck. Yeah, I know, color code, yadda yadda Reverse the wires, reheat and see if needle moves If that still dont work, disconnect wires from the gauge and check for continuity at the wires. By measuring the wires, you are checking the sender and any extension leads and eliminating everything except the gauge. My Westach setup says sender resistance should be about 2.5 ohms for EGT, but meter lead resistance will add to this, so correct reading will be higher. You are really looking for continuity at this point. Now if all appears to be roughly correct, you could turn your digital meter to the millivolt scale, reheat the EGT probe and watch for a tiny millivolt output within seconds of applying flame. The gauge itself can be checked for continuity with a DIGITAL ohmmeter (the gauge is so sensitive that an analog meter can burn the darned thing out). Let me repeat - Test gauge using ONLY a digital ohmmeter Again, you are just looking for continuity, but Westach says somewhere between 8 & 15 ohms. Resistance readings may differ as EGT systems may use either J or K type thermocouples (sender), but you are mainly looking for continuity. These things generally either work well or not at all. Any resistance in the system or any corrosion will generally result in no or very low indication -------- Jerry King Read this topic online here: http://forums.matronics.com/viewtopic.php?p=424509#424509


    Message 2


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 08:05:39 AM PST US
    From: "R&J. Curtis" <RnJCurtis@charter.net>
    Subject: Re: Vans EGT gauge not working...
    > > As far as I know, power to simple analog EGT/CHT indicating systems are > for internal lighting only. > > First of all, it?Ts much easier to test the EGT system by removing the > sender from the exhaust system and heating the tip with a propane torch to > see if you get needle movement ?" need another person in the cockpit to > watch gauge. Please use some precautions here so as to not burn your > airplane nor anyone elses down. A fire extinguisher AND a handy 5 gal > bucket of water along with common sense can work wonders. > > If that didn?Tt work, the next thing to do is reverse the wires and > recheck. Yeah, I know, color code, yadda yadda ?" Reverse the wires, > reheat and see if needle moves > > If that still don?Tt work, disconnect wires from the gauge and check for > continuity at the wires. By measuring the wires, you are checking the > sender and any extension leads and eliminating everything except the > gauge. > > My Westach setup says sender resistance should be about 2.5 ohms for EGT, > but meter lead resistance will add to this, so correct reading will be > higher. You are really looking for continuity at this point. Now if all > appears to be roughly correct, you could turn your digital meter to the > millivolt scale, reheat the EGT probe and watch for a tiny millivolt > output within seconds of applying flame. > > The gauge itself can be checked for continuity with a DIGITAL ohmmeter > (the gauge is so sensitive that an analog meter can burn the darned thing > out). > Let me repeat - Test gauge using ONLY a digital ohmmeter > > Again, you are just looking for continuity, but Westach says somewhere > between 8 & 15 ohms. > > Resistance readings may differ as EGT systems may use either J or K type > thermocouples (sender), but you are mainly looking for continuity. These > things generally either work well or not at all. > > Any resistance in the system or any corrosion will generally result in no > or very low indication Just one other thought on this. If you added an extension wire to the probe MAKE SURE that you used the proper wire. If it is a "J" type, Red and White wires, be certain that you use the red and white thermocouple extension wires. Use of other wires can give you gross errors. Roger


    Message 3


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 09:44:44 AM PST US
    Subject: Re: Tyco W31 switch / breaker
    From: "Eric M. Jones" <emjones@charter.net>
    > However, the person that wired this aircraft originally hooked them up > backwards, with the copper bus bar connected to the "Load" terminal, and > the devices being switched connected to the "Line" terminal. > My question is, does it really matter? Some plumber installed an angle valve that had an arrow on the body. He installed it with the arrow pointing in the wrong direction. How did I learn this? Because the water pressure kept the valve washer stuck to the valve seat so opening the valve unscrewed the washer retaining screw. The valve quit working. Electricians know that a 3-wire flexible cord can only be attached to one end of the cord. Although you might think that a power cord comes out of each end identically, they are actually mirror images. Only one end installs onto (for example) hospital-grade plugs. MAYBE W31 circuit breakers have a proper line and load connection orientation because the conducting parts, arc suppression, hi-voltage withstand, inductive load, capacitance, wet operation, voltage breakdown to ground (or to the toggle), electrical approvals, or God-knows-what-else behaves somewhat differently in the opposite direction. Maybe this matters and maybe not. But if it doesn't matter, why did they mark it that way? Only the P&B/Tyco engineers can tell you and it would certainly be worth an email to find out. Please share it with us. -------- Eric M. Jones www.PerihelionDesign.com 113 Brentwood Drive Southbridge, MA 01550 (508) 764-2072 emjones(at)charter.net Read this topic online here: http://forums.matronics.com/viewtopic.php?p=424516#424516


    Message 4


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 09:53:38 AM PST US
    From: "Robert L. Nuckolls, III" <nuckolls.bob@aeroelectric.com>
    Subject: Re: Vans EGT gauge not working...
    At 06:50 AM 6/8/2014, you wrote: <gki@suffolk.lib.ny.us> > 1) Verified power and ground to the gauge. > As far as I know, power to simple analog EGT/CHT indicating systems are for internal lighting only. Van's line of analog instruments are built on a common frame of circuitry used to position pointers over approx 250 degrees of arc on the dial. Emacs! An exemplar instrument (ammeter) was examined in our shop some years back . . . http://tinyurl.com/mpx8hze This particular device was found to be rather sensitive to strong fields of radio frequency energy in the cockpit . . . First of all, it=99s much easier to test the EGT system by removing the sender from the exhaust system and heating the tip with a propane torch to see if you get needle movement =93 need another person in the cockpit to watch gauge. Please use some precautions here so as to not burn your airplane nor anyone elses down. A fire extinguisher AND a handy 5 gal bucket of water along with common sense can work wonders. If that didn=99t work, the next thing to do is reverse the wires and recheck. Yeah, I know, color code, yadda yadda =93 Reverse the wires, reheat and see if needle moves If that still don=99t work, disconnect wires from the gauge and check for continuity at the wires. By measuring the wires, you are checking the sender and any extension leads and eliminating everything except the gauge. My Westach setup says sender resistance should be about 2.5 ohms for EGT, but meter lead resistance will add to this, so correct reading will be higher. You are really looking for continuity at this point. Now if all appears to be roughly correct, you could turn your digital meter to the millivolt scale, reheat the EGT probe and watch for a tiny millivolt output within seconds of applying flame. The gauge itself can be checked for continuity with a DIGITAL ohmmeter (the gauge is so sensitive that an analog meter can burn the darned thing out). Let me repeat - Test gauge using ONLY a digital ohmmeter Not true . . . the non-electronic instruments designed to read millivolt levels DIRECTLY from a heated thermocouple have VERY low winding resistance as matter of necessity . . . as panel instruments they are generally designed for full scale indication with only tens of millivolts applied to the terminals at TENS of milliamps. "Self powered" instruments of yesteryear were often calibrated assuming thermocouple lead wires long enough to reach to the extreme engine locations on a large airplane. Lead wires for closer engines could be shortened and the lost-resistance compensated for by inserting a "thermocouple spool resistor" in one lead. http://www.dfwairparts.com/images/avionics/Aircraft_Thermocoupl The resistor was shipped with some too-large value (about 10 ohms as I recall). The installing technician could remove the cover and peel off turns of wire on the spools underneath the cover until the desired calibration was achieved. Again, you are just looking for continuity, but Westach says somewhere between 8 & 15 ohms. The input terminal to a Van's EGT will be considerably higher resistance. Signal conditioners inside the instrument are designed for insensitivity to total loop resistance of the thermocouple signal . . . this is goes to the goal of allowing thermocouples to be extended by any practical length without concern for instrument calibration as described above. Bob . . .


    Message 5


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 06:06:01 PM PST US
    Subject: Re: Tyco W31 switch / breaker
    From: Dj Merrill <deej@deej.net>
    On 6/8/2014 12:41 PM, Eric M. Jones wrote: > Only the P&B/Tyco engineers can tell you and it would certainly be worth an email to find out. True, but I had my doubts that I'd find out the answer over the weekend, and waiting until Monday would have cost me an entire day's worth of work on the plane. With the collective wisdom of this group, I figured I had a chance that someone might know. > MAYBE W31 circuit breakers have a proper line and load connection orientation because the conducting parts, arc suppression, hi-voltage withstand, inductive load, capacitance, wet operation, voltage breakdown to ground (or to the toggle), electrical approvals, or God-knows-what-else behaves somewhat differently in the opposite direction. > Yes, this paralleled my own thoughts, and the first thing I did this morning was to re-wire everything the "right" way. It cost a couple of hours of effort, but my anal-retentiveness kept bugging me so it was worth it. Even if they were fine the other way, now my I's are crossed and my T's are dotted... ;-) Thanks for the replies, guys! -Dj -- Dj Merrill - N1JOV - VP EAA Chapter 87 Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/ Glastar Flyer N866RH - http://deej.net/glastar/


    Message 6


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 08:37:11 PM PST US
    From: "Vern Little" <sprocket@vx-aviation.com>
    Subject: Re: Tyco W31 switch / breaker
    Furthermore, if it was important it would be specified in the datasheet, which it is not. Even the writing on the breaker is not specified, so it's technically not part of the device. If you used a breaker to tie two electrical buses together and it had a polarity, what would you do? It doesn't matter with these guys. Vern -----Original Message----- From: Sprocket Sent: Saturday, June 07, 2014 6:24 PM Subject: Re: AeroElectric-List: Tyco W31 switch / breaker It doesn't matter. These are thermal breakers so current direction can run either way. Vern =================================================== Sent from my iThing. It is responsible for all gramma and typo terrors. > On Jun 7, 2014, at 5:50 PM, Dj Merrill <deej@deej.net> wrote: > > > I am in the process of refurbishing the panel in my aircraft, which uses > Tyco W31 switch/breakers for some items > (https://www.aircraftspruce.com/catalog/elpages/pbcircuitbrkr2.php). I > noticed that the W31 terminals are labeled "Line", which I presume is for > the electrical bus, and "Load", which I presume is for the device being > switched. > > However, the person that wired this aircraft originally hooked them up > backwards, with the copper bus bar connected to the "Load" terminal, and > the devices being switched connected to the "Line" terminal. > > My question is, does it really matter? > > If it does, now would be the time to rewire since I have it all apart, > however, the way it is hooked up at present does make for a neater and > cleaner installation. It has been flying this way for over 15 years, but > if it is "wrong", then I should probably make it "right". > > Thanks, > > -Dj > > -- > Dj Merrill - N1JOV - VP EAA Chapter 87 > Sportsman 2+2 Builder #7118 N421DJ - http://deej.net/sportsman/ > Glastar Flyer N866RH - http://deej.net/glastar/ > >


    Message 7


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 09:40:43 PM PST US
    From: Alan Barnett <alansbarnett@verizon.net>
    Subject: Fuse holders
    I need to add circuit protection for my new avionics. I have no room in the panel, so I plan to put fuses behind the panel. I need suggestions for which fuse holder I should use. Is a fuse block preferable to inline fuse holders? What models do you recommend? Thanks for your help. Alan


    Message 8


  • INDEX
  • Back to Main INDEX
  • PREVIOUS
  • Skip to PREVIOUS Message
  • NEXT
  • Skip to NEXT Message
  • LIST
  • Reply to LIST Regarding this Message
  • SENDER
  • Reply to SENDER Regarding this Message
    Time: 09:52:17 PM PST US
    Subject: Re: COZY: Fuse holders
    From: Tim Andres <tim2542@sbcglobal.net>
    ATC or ATM fuses are more durable than glass fuses and are becoming much more common. I'd put them in a device like this from B&C: http://www.bandc.biz/fuseholder8-slot.aspx Tim Andres > On Jun 8, 2014, at 9:39 PM, Alan Barnett <alansbarnett@verizon.net> wrote: > > I need to add circuit protection for my new avionics. I have no room in the panel, so I plan to put fuses behind the panel. I need suggestions for which fuse holder I should use. Is a fuse block preferable to inline fuse holders? What models do you recommend? > > Thanks for your help. > > Alan >




    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
  • 7-Day List Browse
  •   http://www.matronics.com/browse/aeroelectric-list
  • Browse AeroElectric-List 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.

    -- Please support this service by making your Contribution today! --