Thank you Lee and Roland, I deployed a resistor and capacitor as you described and it works perfectly, I have a reduction in voltage (from 14 down to 11) and my contactor runs much cooler. I could probably go a bit more on my resistance (2.7ohms) I think the next step available was 3.3 ohms but it is working to keep it cooler Thank you.
I thought I would ask again for any explanation on how the 0-5k pot works on the zilla to increase voltage (counter-intuitive) and how does the BMS affect that by reducing voltage??? the explanations of what I am seeing is below. Let me know if I need to supply more info. and thanks in advance for any information on the concepts at work here. I am having a little trouble trouble shooting why the Orion BMS is not >> > limiting current. They gave me steps to check on but could I trouble >> > you >> > guys for the explanation of what the zilla hairball does with the >> > throttle >> > pot input? Is that 0 to 5k pot controlling voltage in the hairball? >> > As >> > you step on the pedal the resistance increases and reduces voltage to >> > signal more juice? I would really like to understand what is happening, >> > as >> > it makes it easier to troubleshoot. The Orion BMS has an analog >> > discharge >> > current limit signal that is 0 - 5 volts connecting that through a >> > diode >> > to one side of the pot was the recommended way to hook it up. This is >> > where my brain fuzzes over. I may just have my diode in backwards but >> > I >> > was hoping to get an explanation of how this all works. >> > Thanks so much >> > >> > 92 civic HB 144v Calb 180 SE, Zilla 1k LV, Orion BMS, Elcon 5k >> > charger, >> > 70 mile range to 80% > > > > If that coil has continuous 14V while you are charging (so that > contactor > is continuously pulled in for hours while you are charging) then you are > attempting to burn up that coil - most coils specified for a certain > voltage need an "economizer" (current reducer) when they are engaged for > lengthy periods, such as during charging. > The simplest economizer is a resistor with a large capacitor across, > so the cap causes the full 14V for quick contactor pull-in, then the > coil current charges the cap until there is a balance in voltage > division between coil resistance and the resistor parallel to the cap. > If they are > the same, the current as well as the voltage on the coil will be halved > and the power dissipated in the contactor will be one quart due to the > economizer. Only the resistor will also burn one quart, so you need a > power resistor. More fancy designs use a buck regulator or PWM to reduce > coil voltage. > > Hope this clarifies, > > Cor van de Water > Chief Scientist > Proxim Wireless Corporation http://www.proxim.com > Email: [email protected] Private: http://www.cvandewater.info > Skype: cor_van_de_water Tel: +1 408 383 7626 > >> >> >> >> coil has 14 volts >> I realize that the BMS should have control over that contactor and so my >> charger negative should go on the other side of the contactor (controller >> side rather than battery side) Will that affect the contactor heating? >> >> Also, nobody responded on the bms control question, I flipped the diode >> the other way around and I have no throttle at all. >> Thank you >> >> >> > What is the voltage on the negative contactor coil while charging? >> > >> > Cor van de Water >> > Chief Scientist >> > Proxim Wireless Corporation http://www.proxim.com >> > Email: [email protected] Private: http://www.cvandewater.info >> > Skype: cor_van_de_water Tel: +1 408 383 7626 >> > >> > >> > -----Original Message----- >> > From: [email protected] [mailto:[email protected]] On >> > Behalf Of Mike Malmberg >> > Sent: Sunday, June 23, 2013 6:54 PM >> > To: evdl >> > Subject: [EVDL] contactor heats up while charging + BMS analog control? >> > >> > I hope the amazing brain trust can help me again. >> > I've got my civic running again 144volts of lifepo. I have installed a >> > second contactor on the pack negative of battery pack then to shunt to >> > contactor then contactor to controller - >> > the bms has control over this contactor; the zilla has control over the >> > main contactor on the positive side. >> > Only while charging does this negative contactor get quite hot. the >> > negative of the charger comes in on the pack neg side of the contactor. >> > Juice isn't really running through the contactor or is it? It should be >> > flowing to the battery away from the contactor. the charge wire >> > connected >> > to the contactor isn't particularly warm but the body of the contactor >> > is >> > hot. what is up? charger runs at 30 amps contactor is Tyco Kilovac >> > 500A >> > 320VDC LEV200 >> > >> > 2nd question >> > I am having a little trouble trouble shooting why the Orion BMS is not >> > limiting current. They gave me steps to check on but could I trouble >> > you >> > guys for the explanation of what the zilla hairball does with the >> > throttle >> > pot input? Is that 0 to 5k pot controlling voltage in the hairball? >> > As >> > you step on the pedal the resistance increases and reduces voltage to >> > signal more juice? I would really like to understand what is happening, >> > as >> > it makes it easier to troubleshoot. The Orion BMS has an analog >> > discharge >> > current limit signal that is 0 - 5 volts connecting that through a >> > diode >> > to one side of the pot was the recommended way to hook it up. This is >> > where my brain fuzzes over. I may just have my diode in backwards but >> > I >> > was hoping to get an explanation of how this all works. >> > Thanks so much >> > >> > 92 civic HB 144v Calb 180 SE, Zilla 1k LV, Orion BMS, Elcon 5k >> > charger, >> > 70 mile range to 80% >> > >> > Thanks >> -------------- next part -------------- >> An HTML attachment was scrubbed... >> URL: < >> http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130625/381ffd41/attachment.htm >> > >> >> >> ------------------------------ >> >> >> ------------------------------ >> >> >> >> - >> > -------------- next part -------------- > An HTML attachment was scrubbed... > URL: > <http://lists.evdl.org/private.cgi/ev-evdl.org/attachments/20130626/24816158/attachment.htm> > > > ------------------------------ > > Message: 7 > Date: Wed, 26 Jun 2013 23:27:07 -0700 > From: Mike Malmberg <[email protected]> > To: evdl <[email protected]> > Subject: Re: [EVDL] negative contactor heating up and BMS analogue > control > Message-ID: > <caacrt4xypgejmyxrut5wu5ddqq1hwonw6+uy-kunpvezird...@mail.gmail.com> > Content-Type: text/plain; charset=ISO-8859-1 > > Date: Tue, 25 Jun 2013 22:13:00 -0500 > From: Lee Hart <[email protected]> > To: Electric Vehicle Discussion List <[email protected]> > Subject: Re: [EVDL] EV Digest, Vol 8, Issue 39 > Message-ID: <[email protected]> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Mike Malmberg wrote: my responses below and thank you so much >> coil has 14 volts > > The Tyco LEV200 data sheet says it has a 12vdc coil, and is rated for > 9.6v minimum, 13.2v maximum. 14v is more than its rated voltage, so it > would get hot. > > My suggestion would be to add a series resistor, with a capacitor in > parallel (called a "slugger" circuit). Choose the resistor to drop the > steady-state voltage a few volts. Oddly, the data sheet doesn't give the > coil resistance, so you'll have to measure it or experiment to find the > right resistor value. > > --So a series resistor on positve or negative side of coil. coil > resistance measured with an ohm meter across the coil while the coil > is off or energized? > Is there some math I need to do to calculate the resistor value that I need? > > Then, the capacitor in parallel initially applies the full voltage, to > make the contactor pull in quickly. Something like a 10,000uF > electrolytic capacitor rated at 6vdc or more will do it. > > --And this capacitor goes across the coil of the contactor, yes? > >> I realize that the BMS should have control over that contactor, and so my >> charger negative should go on the other side of the contactor (controller >> side rather than battery side). Will that affect the contactor heating? > > No. You aren't running enough current for its contact to produce any > significant amount of heat. > >> Also, nobody responded on the bms control question, I flipped the diode >> the other way around and I have no throttle at all. > > I can't help you there. Sounds like you had the diode the right way to > begin with. Was it in fact limiting the throttle when the BMS sensed a > low cell voltage? > > --no that was why I started asking questions, it had no effect on the > current output at all. when checking it the original way I had it > hooked up, > I believe I had 5 volts on bms side of the diode and 1.2 volts after > the diode. Does that sound right? > I have gone through the check that Orion recommended which was to pull > the current sensor to see if the BMS responded and it did drop to zero > volts. so full pack 5 volts and no pack 0 volts (.03v ) > > > -- > For every complex problem, there is a solution that is simple, obvious, > and wrong. -- H.L. Mencken > -- > Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm > > > > > Message: 10 > Date: Thu, 27 Jun 2013 00:43:05 -0700 > From: "Cor van de Water" <[email protected]> > To: "Electric Vehicle Discussion List" <[email protected]> > Subject: Re: [EVDL] negative contactor heating up and BMS analogue > control > Message-ID: > <a73bc4b8b3218642a56a2c9eb01b44e001ce2...@exchange.corp.proxim.com> > Content-Type: text/plain; charset="us-ascii" > > The resistor and capacitor are in parallel, then those two are connected > to the contactor coil. There is no difference if they are connected at > the positive or negative side of the contactor coil. The only thing to > check is that the capacitor is oriented the right way, its positive side > to the positive supply that supplies the coil. Just put it in series > with the coil and measure the voltage drop, then verify that the > capacitor + is higher than its negative side. > > Do not put a capacitor across the coil, that will only reduce the speed > of the contactor and cause severe arcing. > > You can measure the contactor coil resistance when it is not active - if > it has a connector then you can pull the connector off and then measure > the coil itself. > > I expect that as soon as the coil resistance is known, Lee or someone > else can make this circuit for you (power resistor + large capacitor) > and send it to you for a small fee. > > Regards, > > Cor van de Water > Chief Scientist > Proxim Wireless Corporation http://www.proxim.com > Email: [email protected] Private: http://www.cvandewater.info > Skype: cor_van_de_water Tel: +1 408 383 7626 > > > -----Original Message----- > From: [email protected] [mailto:[email protected]] On > Behalf Of Mike Malmberg > Sent: Wednesday, June 26, 2013 11:27 PM > To: evdl > Subject: Re: [EVDL] negative contactor heating up and BMS analogue > control > > Date: Tue, 25 Jun 2013 22:13:00 -0500 > From: Lee Hart <[email protected]> > To: Electric Vehicle Discussion List <[email protected]> > Subject: Re: [EVDL] EV Digest, Vol 8, Issue 39 > Message-ID: <[email protected]> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Mike Malmberg wrote: my responses below and thank you so much >> coil has 14 volts > > The Tyco LEV200 data sheet says it has a 12vdc coil, and is rated for > 9.6v minimum, 13.2v maximum. 14v is more than its rated voltage, so it > would get hot. > > My suggestion would be to add a series resistor, with a capacitor in > parallel (called a "slugger" circuit). Choose the resistor to drop the > steady-state voltage a few volts. Oddly, the data sheet doesn't give the > coil resistance, so you'll have to measure it or experiment to find the > right resistor value. > > --So a series resistor on positve or negative side of coil. coil > resistance measured with an ohm meter across the coil while the coil > is off or energized? > Is there some math I need to do to calculate the resistor value that I > need? > > Then, the capacitor in parallel initially applies the full voltage, to > make the contactor pull in quickly. Something like a 10,000uF > electrolytic capacitor rated at 6vdc or more will do it. > > --And this capacitor goes across the coil of the contactor, yes? > >> I realize that the BMS should have control over that contactor, and so > my >> charger negative should go on the other side of the contactor > (controller >> side rather than battery side). Will that affect the contactor > heating? > > No. You aren't running enough current for its contact to produce any > significant amount of heat. > >> Also, nobody responded on the bms control question, I flipped the > diode >> the other way around and I have no throttle at all. > > I can't help you there. Sounds like you had the diode the right way to > begin with. Was it in fact limiting the throttle when the BMS sensed a > low cell voltage? > > --no that was why I started asking questions, it had no effect on the > current output at all. when checking it the original way I had it > hooked up, > I believe I had 5 volts on bms side of the diode and 1.2 volts after > the diode. Does that sound right? > I have gone through the check that Orion recommended which was to pull > the current sensor to see if the BMS responded and it did drop to zero > volts. so full pack 5 volts and no pack 0 volts (.03v ) > > > -- > For every complex problem, there is a solution that is simple, obvious, > and wrong. -- H.L. Mencken > -- > Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm > _______________________________________________ > UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub > http://lists.evdl.org/listinfo.cgi/ev-evdl.org > For EV drag racing discussion, please use NEDRA > (http://groups.yahoo.com/group/NEDRA) > > > > ------------------------------ > > Message: 11 > Date: Thu, 27 Jun 2013 08:03:26 -0500 > From: Lee Hart <[email protected]> > To: Electric Vehicle Discussion List <[email protected]> > Subject: Re: [EVDL] negative contactor heating up and BMS analogue > control > Message-ID: <[email protected]> > Content-Type: text/plain; charset=ISO-8859-1; format=flowed > > Lee Hart wrote: >> My suggestion would be to add a series resistor, with a capacitor in >> parallel (called a "slugger" circuit)... > > Mike Malmberg wrote: >> --So a series resistor on positive or negative side of coil? > > It doesn't matter. The resistor goes in series with either coil wire. > > Without the resistor, you see 14v across the coil with it on. Choose the > resistance value so you get about 10v across the coil, and 4v across the > resistor. > > Then, wire the capacitor across the resistor (not the coil). The > capacitor has a polarity; connect it so your meter shows a positive > voltage across it (with your meter red + lead on the capacitor +, and > the meter black - lead on the capacitor -). > > The capacitor should be rated at about 10,000uF (the value is not > critical -- 2:1 either side of this is fine). It should be rated for > 16vdc or more. > > The Tyco data sheet doesn't tell me the coil resistance; you'll have to > measure it with your meter. Then the resistor value is about 4/14th of > the coil resistance. For example, if your coil measures 10 ohms, then > the resistor is 10ohms x 4 / 14 = 2.85 ohms. Again, it's not critical; > anything from 2 to 3.5 ohms will work. Since the coil draws about an > amp, the resistor needs to dissipate power; about (4v)^2 / R. If your > resistor is 4 ohms, that's 4^2 / 4 = 16 / 4 = 4 watts; so use a 10 watt > resistor. > > If you can tell me the coil resistance, I can send you the parts. The > postage costs more than the parts do! > > -- > For every complex problem, there is a solution that is simple, obvious, > and wrong. -- H.L. Mencken > -- > Lee A. Hart, http://www.sunrise-ev.com/LeesEVs.htm > > > _______________________________________________ UNSUBSCRIBE: http://www.evdl.org/help/index.html#usub http://lists.evdl.org/listinfo.cgi/ev-evdl.org For EV drag racing discussion, please use NEDRA (http://groups.yahoo.com/group/NEDRA)
