---------------------------------------------------------- AeroElectric-List Digest Archive --- Total Messages Posted Wed 01/17/18: 10 ---------------------------------------------------------- Today's Message Index: ---------------------- 1. 03:58 PM - diode on starter contactor (Ken Ryan) 2. 04:10 PM - Re: diode on starter contactor (Alec Myers) 3. 04:16 PM - Re: diode on starter contactor (user9253) 4. 04:19 PM - Re: diode on starter contactor (Ken Ryan) 5. 04:34 PM - Re: diode on starter contactor (Charlie England) 6. 04:36 PM - Re: diode on starter contactor (Alec Myers) 7. 05:39 PM - Re: diode on starter contactor (Ken Ryan) 8. 09:50 PM - Re: diode on starter contactor (Bernie) 9. 11:00 PM - Re: diode on starter contactor (Bill Bear) 10. 11:27 PM - Re: diode on starter contactor (Bernie Willis) ________________________________ Message 1 _____________________________________ Time: 03:58:07 PM PST US From: Ken Ryan Subject: AeroElectric-List: diode on starter contactor My starter contactor's coil gets its ground through the contactor's metal case. Given that, does it make any sense to use a diode? If so, how would that diode be implemented and how would it remain effective when the case itself is the ground path? Ken ________________________________ Message 2 _____________________________________ Time: 04:10:55 PM PST US From: Alec Myers Subject: Re: AeroElectric-List: diode on starter contactor Wire it across the coil, so from non ground terminal to ground terminal, so its reverse polarized when the coil is energized. Then when power is removed, the magnetic field collapses driving current through the diode and avoiding a large back emf. If you put it the wrong way round, dont worry, it will just disappear. On Jan 17, 2018, at 18:56, Ken Ryan wrote: My starter contactor's coil gets its ground through the contactor's metal case. Given that, does it make any sense to use a diode? If so, how would that diode be implemented and how would it remain effective when the case itself is the ground path? Ken ________________________________ Message 3 _____________________________________ Time: 04:16:20 PM PST US Subject: AeroElectric-List: Re: diode on starter contactor From: "user9253" An arc suppression diode should be connected directly across a coil. It is best if the diode is located at the coil. If that is impractical for some reason, then the diode can be located farther away as long as it is still connected in parallel with the coil. The banded end of the diode must be connected to the positive coil terminal and the other end of the diode connects to the negative terminal of the coil. If the coil is internally connected to the case, then the diode should be connected to the case or any convenient ground, assuming that the case is grounded. -------- Joe Gores Read this topic online here: http://forums.matronics.com/viewtopic.php?p=477380#477380 ________________________________ Message 4 _____________________________________ Time: 04:19:19 PM PST US From: Ken Ryan Subject: Re: AeroElectric-List: diode on starter contactor Alec, like I said in my original post, there is no ground terminal. Ground is accomplished through the metal case. On Wed, Jan 17, 2018 at 3:10 PM, Alec Myers wrote: > > Wire it across the coil, so from non ground terminal to ground terminal, > so it=99s reverse polarized when the coil is energized. Then when p ower is > removed, the magnetic field collapses driving current through the diode a nd > avoiding a large back emf. > > If you put it the wrong way round, don=99t worry, it will just disa ppear. > > > On Jan 17, 2018, at 18:56, Ken Ryan wrote: > > My starter contactor's coil gets its ground through the contactor's metal > case. Given that, does it make any sense to use a diode? If so, how would > that diode be implemented and how would it remain effective when the case > itself is the ground path? > > Ken > > =========== =========== =========== =========== =========== > > ________________________________ Message 5 _____________________________________ Time: 04:34:02 PM PST US Subject: Re: AeroElectric-List: diode on starter contactor From: Charlie England Think of the contactor's mounting screw as the ground terminal (it actually *is* the ground terminal). So the banded end of the diode is connected to the control terminal, and the unbanded end is connected to one of the mounting screws. Or as others have said, any convenient grounded terminal nearby. Note that you can solder or crimp a short length of wire to either/both leads on the diode, and solder or crimp ring terminals to the wire, if the diode's leads aren't long enough to reach where they need to go. Just slip some heat shrink tubing, or even wire insulation stripped off a bigger wire, over the exposed leads as needed to keep the 'hot' end isolated from ground. On 1/17/2018 6:18 PM, Ken Ryan wrote: > Alec, like I said in my original post, there is no ground terminal. > Ground is accomplished through the metal case. > > On Wed, Jan 17, 2018 at 3:10 PM, Alec Myers > wrote: > > > > > Wire it across the coil, so from non ground terminal to ground > terminal, so its reverse polarized when the coil is energized. > Then when power is removed, the magnetic field collapses driving > current through the diode and avoiding a large back emf. > > If you put it the wrong way round, dont worry, it will just > disappear. > > > On Jan 17, 2018, at 18:56, Ken Ryan > wrote: > > My starter contactor's coil gets its ground through the > contactor's metal case. Given that, does it make any sense to use > a diode? If so, how would that diode be implemented and how would > it remain effective when the case itself is the ground path? > > Ken > --- This email has been checked for viruses by Avast antivirus software. https://www.avast.com/antivirus ________________________________ Message 6 _____________________________________ Time: 04:36:17 PM PST US From: Alec Myers Subject: Re: AeroElectric-List: diode on starter contactor Use the mounting bolt then, with a ring terminal under the bolt head. > On Jan 17, 2018, at 19:18, Ken Ryan wrote: > > Alec, like I said in my original post, there is no ground terminal. Ground is accomplished through the metal case. > >> On Wed, Jan 17, 2018 at 3:10 PM, Alec Myers wrote: >> >> Wire it across the coil, so from non ground terminal to ground terminal, s o it=99s reverse polarized when the coil is energized. Then when power is removed, the magnetic field collapses driving current through the diode a nd avoiding a large back emf. >> >> If you put it the wrong way round, don=99t worry, it will just disa ppear. >> >> >> >> On Jan 17, 2018, at 18:56, Ken Ryan wrote: >> >> My starter contactor's coil gets its ground through the contactor's metal case. Given that, does it make any sense to use a diode? If so, how would t hat diode be implemented and how would it remain effective when the case its elf is the ground path? >> >> Ken >> >> >> ========================= ============ >> - >> Electric-List" rel="noreferrer" target="_blank">http://www.matronics. com/Navigator?AeroElectric-List >> ========================= >> FORUMS - >> eferrer" target="_blank">http://forums.matronics.com >> ========================= >> WIKI - >> errer" target="_blank">http://wiki.matronics.com >> ========================= >> b Site - >> -Matt Dralle, List Admin. >> rel="noreferrer" target="_blank">http://www.matronics.com/contributio n >> ========================= >> >> >> > ________________________________ Message 7 _____________________________________ Time: 05:39:59 PM PST US From: Ken Ryan Subject: Re: AeroElectric-List: diode on starter contactor Thanks everyone. On Wed, Jan 17, 2018 at 3:35 PM, Alec Myers wrote: > Use the mounting bolt then, with a ring terminal under the bolt head. > > On Jan 17, 2018, at 19:18, Ken Ryan wrote: > > Alec, like I said in my original post, there is no ground terminal. Groun d > is accomplished through the metal case. > > On Wed, Jan 17, 2018 at 3:10 PM, Alec Myers wrote: > >> >> Wire it across the coil, so from non ground terminal to ground terminal, >> so it=99s reverse polarized when the coil is energized. Then when power is >> removed, the magnetic field collapses driving current through the diode and >> avoiding a large back emf. >> >> If you put it the wrong way round, don=99t worry, it will just dis appear. >> >> >> >> On Jan 17, 2018, at 18:56, Ken Ryan wrote: >> >> My starter contactor's coil gets its ground through the contactor's meta l >> case. Given that, does it make any sense to use a diode? If so, how woul d >> that diode be implemented and how would it remain effective when the cas e >> itself is the ground path? >> >> Ken >> >> >> ======================== ============= >> - >> Electric-List" rel="noreferrer" target="_blank">http://www.matronics .com/ >> Navigator?AeroElectric-List >> ======================== =========== >> FORUMS - >> eferrer" target="_blank">http://forums.matronics.com >> ======================== =========== >> WIKI - >> errer" target="_blank">http://wiki.matronics.com >> ======================== =========== >> b Site - >> -Matt Dralle, List Admin. >> rel="noreferrer" target="_blank">http://www.matronics.com/contributi on >> ======================== =========== >> >> >> >> > ________________________________ Message 8 _____________________________________ Time: 09:50:37 PM PST US From: Bernie Subject: Re: AeroElectric-List: diode on starter contactor I=99m trying to follow the diode and the starter sol. discussion. I mi ssed the reason for the diode. Thanks Bernie Sent from my iPhone > On Jan 17, 2018, at 4:38 PM, Ken Ryan wrote: > > Thanks everyone. > > >> On Wed, Jan 17, 2018 at 3:35 PM, Alec Myers wrote: >> Use the mounting bolt then, with a ring terminal under the bolt head. >> >>> On Jan 17, 2018, at 19:18, Ken Ryan wrote: >>> >>> Alec, like I said in my original post, there is no ground terminal. Grou nd is accomplished through the metal case. >>> >>>> On Wed, Jan 17, 2018 at 3:10 PM, Alec Myers wrote: > >>>> >>>> Wire it across the coil, so from non ground terminal to ground terminal , so it=99s reverse polarized when the coil is energized. Then when po wer is removed, the magnetic field collapses driving current through the dio de and avoiding a large back emf. >>>> >>>> If you put it the wrong way round, don=99t worry, it will just di sappear. >>>> >>>> >>>> >>>> On Jan 17, 2018, at 18:56, Ken Ryan wrote: >>>> >>>> My starter contactor's coil gets its ground through the contactor's met al case. Given that, does it make any sense to use a diode? If so, how would that diode be implemented and how would it remain effective when the case i tself is the ground path? >>>> >>>> Ken >>>> >>>> >>>> ============ >>>> - >>>> Electric-List" rel="noreferrer" target="_blank">http://www.matronic s.com/Navigator?AeroElectric-List >>>> ========== >>>> FORUMS - >>>> eferrer" target="_blank">http://forums.matronics.com >>>> ========== >>>> WIKI - >>>> errer" target="_blank">http://wiki.matronics.com >>>> ========== >>>> b Site - >>>> -Matt Dralle, List Admin. >>>> rel="noreferrer" target="_blank">http://www.matronics.com/contribut ion >>>> ========== >>>> >>>> >>>> >>> > ________________________________ Message 9 _____________________________________ Time: 11:00:59 PM PST US From: Bill Bear Subject: Re: AeroElectric-List: diode on starter contactor Bernie, As I understand it, when the solenoid is deenergized, a voltage surge peak passes through the circuit which ages the solenoid contacts. The diode prevents the passage of the surge current and lengthens the life of the solenoid contacts. The diode band end is connected to the positive side of the solenoid contractor and the other side of the diode is connected to ground at the solenoid. Bill > On Jan 17, 2018, at 20:49, Bernie wrote: > > I=99m trying to follow the diode and the starter sol. discussion. I missed the reason for the diode. > > Thanks > Bernie > > Sent from my iPhone > > On Jan 17, 2018, at 4:38 PM, Ken Ryan > wrote: > >> Thanks everyone. >> >> >> On Wed, Jan 17, 2018 at 3:35 PM, Alec Myers > wrote: >> Use the mounting bolt then, with a ring terminal under the bolt head. >> >> On Jan 17, 2018, at 19:18, Ken Ryan > wrote: >> >>> Alec, like I said in my original post, there is no ground terminal. Ground is accomplished through the metal case. >>> >>> On Wed, Jan 17, 2018 at 3:10 PM, Alec Myers > wrote: > >>> >>> Wire it across the coil, so from non ground terminal to ground terminal, so it=99s reverse polarized when the coil is energized. Then when power is removed, the magnetic field collapses driving current through the diode and avoiding a large back emf. >>> >>> If you put it the wrong way round, don=99t worry, it will just disappear. >>> >>> >>> >>> On Jan 17, 2018, at 18:56, Ken Ryan > wrote: >>> >>> My starter contactor's coil gets its ground through the contactor's metal case. Given that, does it make any sense to use a diode? If so, how would that diode be implemented and how would it remain effective when the case itself is the ground path? >>> >>> Ken >>> >>> >>> ============ >>> - >>> Electric-List" rel="noreferrer" target="_blank">http://www.matronics.com/ Navigator?AeroElectric-List >>> ========== >>> FORUMS - >>> eferrer" target="_blank">http://forums.matronics.com >>> ========== >>> WIKI - >>> errer" target="_blank">http://wiki.matronics.com >>> ========== >>> b Site - >>> -Matt Dralle, List Admin. >>> rel="noreferrer" target="_blank">http://www.matronics.com/ contribution >>> ========== >>> >>> >>> >>> >> ________________________________ Message 10 ____________________________________ Time: 11:27:53 PM PST US From: Bernie Willis Subject: Re: AeroElectric-List: diode on starter contactor Bill, That refinement to the traditional circuit makes sense. Is there any particular diode? Thanks, Bernie > On Jan 17, 2018, at 9:59 PM, Bill Bear wrote: > > Bernie, > > As I understand it, when the solenoid is deenergized, a voltage surge peak passes through the circuit which ages the solenoid contacts. The diode prevents the passage of the surge current and lengthens the life of the solenoid contacts. The diode band end is connected to the positive side of the solenoid contractor and the other side of the diode is connected to ground at the solenoid. > > Bill > > >> On Jan 17, 2018, at 20:49, Bernie > wrote: >> >> I=99m trying to follow the diode and the starter sol. discussion. I missed the reason for the diode. >> >> Thanks >> Bernie >> >> Sent from my iPhone >> >> On Jan 17, 2018, at 4:38 PM, Ken Ryan > wrote: >> >>> Thanks everyone. >>> >>> >>> On Wed, Jan 17, 2018 at 3:35 PM, Alec Myers > wrote: >>> Use the mounting bolt then, with a ring terminal under the bolt head. >>> >>> On Jan 17, 2018, at 19:18, Ken Ryan > wrote: >>> >>>> Alec, like I said in my original post, there is no ground terminal. Ground is accomplished through the metal case. >>>> >>>> On Wed, Jan 17, 2018 at 3:10 PM, Alec Myers > wrote: > >>>> >>>> Wire it across the coil, so from non ground terminal to ground terminal, so it=99s reverse polarized when the coil is energized. Then when power is removed, the magnetic field collapses driving current through the diode and avoiding a large back emf. >>>> >>>> If you put it the wrong way round, don=99t worry, it will just disappear. >>>> >>>> >>>> >>>> On Jan 17, 2018, at 18:56, Ken Ryan > wrote: >>>> >>>> My starter contactor's coil gets its ground through the contactor's metal case. Given that, does it make any sense to use a diode? If so, how would that diode be implemented and how would it remain effective when the case itself is the ground path? >>>> >>>> Ken >>>> >>>> >>>> ============ >>>> - >>>> Electric-List" rel="noreferrer" target="_blank">http://www.matronics.com/ Navigator?AeroElectric-List >>>> ========== >>>> FORUMS - >>>> eferrer" target="_blank">http://forums.matronics.com >>>> ========== >>>> WIKI - >>>> errer" target="_blank">http://wiki.matronics.com >>>> ========== >>>> b Site - >>>> -Matt Dralle, List Admin. >>>> rel="noreferrer" target="_blank">http://www.matronics.com/ contribution >>>> ========== >>>> >>>> >>>> >>>> >>> > ------------------------------------------------------------------------------------- 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.