---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 12/17/14: 11 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 02:51 AM - Re: Wiring dual fuel pumps to single switch (carrollcw) 2. 07:39 AM - Re: Wiring dual fuel pumps to single switch (Justin Jones) 3. 07:58 AM - Re: Wiring dual fuel pumps to single switch (John Tipton) 4. 08:38 AM - Re: Re: Wiring dual fuel pumps to single switch (Charlie England) 5. 08:58 AM - Re: Re: Wiring dual fuel pumps to single switch (Robert L. Nuckolls, III) 6. 09:02 AM - Re: Re: Wiring dual fuel pumps to single switch (Jeff Luckey) 7. 10:11 AM - Re: Re: Wiring dual fuel pumps to single switch (Charlie England) 8. 05:24 PM - stacking ring terminals on terminal post (Ken Ryan) 9. 05:38 PM - Re: stacking ring terminals on terminal post (Joe Motis) 10. 06:03 PM - Re: stacking ring terminals on terminal post (BobsV35B@aol.com) 11. 10:20 PM - Re: stacking ring terminals on terminal post (Chuck Birdsall) ________________________________ Message 1 _____________________________________ Time: 02:51:07 AM PST US Subject: AeroElectric-List: Re: Wiring dual fuel pumps to single switch From: "carrollcw" Ceengland, if you posted a picture, it's not showing up for me. Read this topic online here: http://forums.matronics.com/viewtopic.php?p=435804#435804 ________________________________ Message 2 _____________________________________ Time: 07:39:39 AM PST US From: Justin Jones Subject: Re: AeroElectric-List: Wiring dual fuel pumps to single switch If you don=92t want to do it with 2 separate switches, I would suggest looking at a rotary switch. Pay attention to the switch amperage ratings as it may require a relay to drive a fuel pump. Keep in mind that with this option, you will not have the ability to turn both pumps on simultaneously. The 2 switches below may work. http://www.digikey.com/product-detail/en/MRT23-A/360-2376-ND/1046092 http://www.digikey.com/product-detail/en/HS13Y-D/360-2350-ND/2039688 link to the knob for this switch ( http://www.digikey.com/product-detail/en/AT432/360-2366-ND/639088 ) There are many more options out there for rotary switches. Hope this helps Justin > On Dec 16, 2014, at 5:03 PM, carrollcw wrote: > > > How can I wire a single dual pole switch to control 2 fuel pumps, only one of which can operate at once with the switch being off bottom, pump 1 middle, pump 2 top. I also need each pump to have an independent power source. I thought I could do it with a 2-1, but I can only get it to go on-off-on. Is there a dual pole switch that will accomplish this? > > > > > Read this topic online here: > > http://forums.matronics.com/viewtopic.php?p=435793#435793 > > > > > > > > > > ________________________________ Message 3 _____________________________________ Time: 07:58:36 AM PST US Subject: Re: AeroElectric-List: Wiring dual fuel pumps to single switch From: John Tipton What you want to do is achievable (I believe) with a 2-10, which is an ON-ON -ON - 2 Pole - so wire as you will see here: Ebay: 131380680747 Or 'Steinair' John Sent from my iPad ----x--O--x---- > On 17 Dec 2014, at 03:37 pm, Justin Jones wro te: > > If you don=99t want to do it with 2 separate switches, I would sugge st looking at a rotary switch. Pay attention to the switch amperage ratings as it may require a relay to drive a fuel pump. Keep in mind that with thi s option, you will not have the ability to turn both pumps on simultaneously . > > The 2 switches below may work. > > http://www.digikey.com/product-detail/en/MRT23-A/360-2376-ND/1046092 > > > http://www.digikey.com/product-detail/en/HS13Y-D/360-2350-ND/2039688 link to the knob for this switch ( http://www.digikey.com/product-detail/en/AT4 32/360-2366-ND/639088 ) > > > > There are many more options out there for rotary switches. > > Hope this helps > > Justin > > >> On Dec 16, 2014, at 5:03 PM, carrollcw wrote: >> m> >> >> How can I wire a single dual pole switch to control 2 fuel pumps, only on e of which can operate at once with the switch being off bottom, pump 1 midd le, pump 2 top. I also need each pump to have an independent power source. I thought I could do it with a 2-1, but I can only get it to go on-off-on. Is there a dual pole switch that will accomplish this? >> >> >> >> >> Read this topic online here: >> >> http://forums.matronics.com/viewtopic.php?p=435793#435793 > > > 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D 3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3 D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D =3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D=3D > ________________________________ Message 4 _____________________________________ Time: 08:38:29 AM PST US From: Charlie England Subject: Re: AeroElectric-List: Re: Wiring dual fuel pumps to single switch On 12/17/2014 4:49 AM, carrollcw wrote: > > Ceengland, if you posted a picture, it's not showing up for me. > > No pic; just a reminder that using one switch means a potential single point of failure for both fuel pumps. Might be acceptably low risk, but should be considered. ________________________________ Message 5 _____________________________________ Time: 08:58:07 AM PST US From: "Robert L. Nuckolls, III" Subject: Re: AeroElectric-List: Re: Wiring dual fuel pumps to single switch At 10:38 2014-12-17, you wrote: > > >On 12/17/2014 4:49 AM, carrollcw wrote: >> >>Ceengland, if you posted a picture, it's not showing up for me. >> >No pic; just a reminder that using one switch means a potential >single point of failure for both fuel pumps. Might be acceptably low >risk, but should be considered. As John mentioned, you can wire a =10 style toggle switch to offer single pole, three position functionality as described in chapter 11 of the 'Connection. Here is one example of this technique. Emacs! A single-pole, three position, center-off will work too . . . but this makes the switch different from all the rest in that OFF is not fully down but mid-position. Charlie's question goes to the notion that if you have two such pumps, then we assume that one must be operational at all times to keep the engine running . . . hence a spare pump. If this is true, then consider the fact that the pump can fail to work for a host of reasons . . . broken wire, bad switch, blown fuse, etc. If one pump circuit goes bad and pops the fuse, then the single failure may take down both pumps. The legacy failure mode effects analysis suggests that the two pumps are best installed as totally separate entities with dedicated switches and power sources. Bob . . . ________________________________ Message 6 _____________________________________ Time: 09:02:11 AM PST US From: Jeff Luckey Subject: Re: AeroElectric-List: Re: Wiring dual fuel pumps to single switch If you're taking a poll... I add my vote to what Charlie said. One switch is a single point of failure - if it fails you could lose both pumps. Just occurred to me: Do you have a situation where you want to prevent both pumps from being on simultaneously? Could use a mechanical interlock between 2 switches if that is the case. -Jeff On Wednesday, December 17, 2014 8:53 AM, Charlie England wrote: On 12/17/2014 4:49 AM, carrollcw wrote: > > Ceengland, if you posted a picture, it's not showing up for me. > > No pic; just a reminder that using one switch means a potential single point of failure for both fuel pumps. Might be acceptably low risk, but should be considered. ________________________________ Message 7 _____________________________________ Time: 10:11:45 AM PST US Subject: Re: AeroElectric-List: Re: Wiring dual fuel pumps to single switch From: Charlie England On Wed, Dec 17, 2014 at 10:54 AM, Robert L. Nuckolls, III < nuckolls.bob@aeroelectric.com> wrote: > > At 10:38 2014-12-17, you wrote: > > ceengland7@gmail.com> > > On 12/17/2014 4:49 AM, carrollcw wrote: > > > > > Ceengland, if you posted a picture, it's not showing up for me. > > No pic; just a reminder that using one switch means a potential single > point of failure for both fuel pumps. Might be acceptably low risk, but > should be considered. > > > As John mentioned, you can wire a =10 style toggle > switch to offer single pole, three position functionality > as described in chapter 11 of the 'Connection. > > Here is one example of this technique. > > > [image: Emacs!] > > > A single-pole, three position, center-off will > work too . . . but this makes the switch different > from all the rest in that OFF is not fully down > but mid-position. > > Charlie's question goes to the notion that if > you have two such pumps, then we assume that one > must be operational at all times to keep the engine > running . . . hence a spare pump. If this is > true, then consider the fact that the pump > can fail to work for a host of reasons . . . > broken wire, bad switch, blown fuse, etc. > If one pump circuit goes bad and pops the fuse, > then the single failure may take down both > pumps. > > The legacy failure mode effects analysis > suggests that the two pumps are best installed > as totally separate entities with dedicated > switches and power sources. > > Bob . . . > I think he spec'd separate power sources for each pump. But a mechanical failure (cracked housing allowing the switch to fall apart, etc), while admittedly rather low risk for a quality switch, could still take out both pumps. ________________________________ Message 8 _____________________________________ Time: 05:24:20 PM PST US From: Ken Ryan Subject: AeroElectric-List: stacking ring terminals on terminal post What's the accepted practice for stacking ring terminals on a terminal post? Rotax 914 diagram shows 5 wires coming together at a capacitor. What's the best way to make that connection? ________________________________ Message 9 _____________________________________ Time: 05:38:22 PM PST US Subject: Re: AeroElectric-List: stacking ring terminals on terminal post From: Joe Motis With new star washers and noalox? 2/3 more than that?? uh uh.. One man's opinion On Wed, Dec 17, 2014 at 5:21 PM, Ken Ryan wrote: > > What's the accepted practice for stacking ring terminals on a terminal > post? Rotax 914 diagram shows 5 wires coming together at a capacitor. > What's the best way to make that connection? > > * > > > * > > ________________________________ Message 10 ____________________________________ Time: 06:03:39 PM PST US From: BobsV35B@aol.com Subject: Re: AeroElectric-List: stacking ring terminals on terminal post Don't know what is being taught these days, but when I went through Aviation Electricians Mate school in 1947 we were told no more than three ring terminals per post. No star washers were to be used because they interfered with good clean contact. Happy Skies, Old Bob Corporal USMC 646659 AEM In a message dated 12/17/2014 7:25:57 P.M. Central Standard Time, keninalaska@gmail.com writes: What's the accepted practice for stacking ring terminals on a terminal post? Rotax 914 diagram shows 5 wires coming together at a capacitor. What's the best way to make that connection? ________________________________ Message 11 ____________________________________ Time: 10:20:58 PM PST US From: Chuck Birdsall Subject: Re: AeroElectric-List: stacking ring terminals on terminal post Currently being taught is no more than 4 terminals per post. If more connections are needed, then use two posts with a buss bar connecting the two of them - and no more than 3 terminals plus the buss bar per post. Reference is AC 43.13-1B Chapter 11 Sections 8 & 14. See also the section beginning at page 98 in this training manual: http://www.keybridgeti.com/videotraining/manualdl/25827.PDF (which includes a discussion about washers). So, to answer the question directly - in my mind, the standard method would be to terminate all five wires with a ring terminal. Use two adjacent terminal posts on a terminal strip, bridge them with a buss bar and attach two terminals to one post and three to the other. Alternatively you could make a short jumper wire with a terminal on each end, and use it to bridge two posts (you'll wind up with 4 terminals on one post and 3 on the other). *(Wires and/or buss bars sized appropriately for the current load.) Now I'm going to muddy the water a bit. 43.13-1B does say that more than 4 terminals can be placed on a post IF specifically authorized. In the Type-Certificated world that I live in, it's much easier to just wire it to the standard (4 or less per post) than it is to go get approval to do it differently - unless there is an "approved" source (such as an install manual for an STC'd item) telling me to do it differently. Chuck On 12/17/2014 8:02 PM, BobsV35B@aol.com wrote: > Don't know what is being taught these days, but when I went through > Aviation Electricians Mate school in 1947 we were told no more than > three ring terminals per post. No star washers were to be used because > they interfered with good clean contact. > Happy Skies, > Old Bob > Corporal USMC 646659 AEM > In a message dated 12/17/2014 7:25:57 P.M. Central Standard Time, > keninalaska@gmail.com writes: > > What's the accepted practice for stacking ring terminals on a > terminal post? Rotax 914 diagram shows 5 wires coming together at > a capacitor. What's the best way to make that connection? > > * > > * > > * > * ------------------------------------------------------------------------------------- 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.