# Contactors for 156-168v+



## booksix (Aug 26, 2008)

I was just scanning a few EV suppliers looking for contactors. The highest I found was a 96v unit which the supplier (not the manufacturer) ok'd up to 156v. But what are people using above that?

Also, how would I know what to grab if I was gonna run some used lift contactors in parallel?


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## TX_Dj (Jul 25, 2008)

The caveat I see with using contactors in parallel is that the contacts are not rated for the volt/amps of the system, so if one fails to engage, the other will be more likely to weld the contacts when it engages or disengages, especially under load.

The main point of the contactor's rated volts/amps is what they can sustain without becoming a permanent connection. 

The other rating is the actuation coil, which can be 12v you can find it, or more likely rated for pack volts with a KSI relay to actuate it from the stock electrical system.

Check www.mouser.com, they have tons of relays. Search for kilovac and albright, they're the two big names in heavy duty contactors.


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## booksix (Aug 26, 2008)

Thanks for the suggestion! But for some reason, I can't find any 'high voltage' contactors at mouser.com. I seem to find nothing about 48v


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## major (Apr 4, 2008)

booksix said:


> I seem to find nothing about 48v


Hi booksix,

http://relays.tycoelectronics.com/datasheets/ev200.pdf 

This Kilovac works well.

major


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## booksix (Aug 26, 2008)

Looks like a great unit! Small, 12v coil. Price tag is pretty high though., especially when you need two.

edit: nm, they can be found cheaper with some searching.

Another question, do most people get w/ aux connections? What exactly does this allow you to monitor?


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## major (Apr 4, 2008)

booksix said:


> Another question, do most people get w/ aux connections? What exactly does this allow you to monitor?


Hi book6,

Aux contacts close when the main contacts are closed, but are an isolated circuit. Often used for a confirmation signal sent back to the control logic to make sure main power is there before starting the motor circuit pulsing. For instance, if you had a precharge resistor across the main contacts, you'd have voltage on the buss caps and the logic might think it was good to go even if the main contacts were open for some reason. The confirmation signal leaves no doubt.

Regards,

major


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## booksix (Aug 26, 2008)

Got it, thanks!!


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## booksix (Aug 26, 2008)

Ok, so what about a reversing contactor that can take 156v and 600-700 amps? I'm planning a dual 9 series/parallel with single motor electric reverse...


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## major (Apr 4, 2008)

booksix said:


> Ok, so what about a reversing contactor that can take 156v and 600-700 amps? I'm planning a dual 9 series/parallel with single motor electric reverse...


Hey book6,

I think a lot of guys run Albright.

Reagrds,

major


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## frodus (Apr 12, 2008)

http://www.wesgarde.com/newproduct_Kilivac.shtml

$99


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## booksix (Aug 26, 2008)

thanks, but i was trying to plan ahead and I can't see the Albright reversing unit standing up to 1000+ amp launches. Anyone know what is in white zombie for reversing?


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## frodus (Apr 12, 2008)

http://www.evparts.com/prod-SL2586.htm

allbright will do 1000A for 1minute

White Zombie has dual motors, and it looks like (after a brief read on the site) that he has one contactor to disengage the field, and another to connect reverse.... but its unclear. Look like SW200's


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## booksix (Aug 26, 2008)

1000 amps for 1 minute? For some reason I thought I read 450 for 30 seconds. Anyway, I am planning to kill one motor during reverse as well (through the use of the three series/parallel contactors I'm planning - the kilovacs)


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## frodus (Apr 12, 2008)

just remember, if there's any advancing on the motor, you'll blow it up if you run it too high in reverse.... it'l start arcing VERY badly.


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## booksix (Aug 26, 2008)

10 degrees. But until your comment. Thought I'd be ok (just backing out of paring spaces) but I guess I have no clue. What is the reality of this setup? Reversing a 10 degree advance motor through a 3.15:1 rear diff...?


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## frodus (Apr 12, 2008)

it'l be fine, as long as you don't go 100% of the motor speed at full voltage.


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## major (Apr 4, 2008)

booksix said:


> 10 degrees. But until your comment. Thought I'd be ok (just backing out of paring spaces) but I guess I have no clue. What is the reality of this setup? Reversing a 10 degree advance motor through a 3.15:1 rear diff...?


Probably low speed reverse travel would not cause any flashover problems. However, on a grade (backing up hill) or wheel spin might be a problem. It would be the high voltage, high speed, and/or high current causing problems. Could be a reason to design it to use the 2 motors in series for reverse. Probably not needed if you're careful with backing up.

Opinion, not experience speaking.

major


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## booksix (Aug 26, 2008)

So what you're saying is I'll no longer be able to mimic the chase scene from Gone in Sixty Seconds?!? Bummer! LOL

As for dual motor reverse in series, wouldn't that only limit to speed (already way to fast for reversing) due to half voltage? Because it's much cheaper to run only one reversing contactor and have the second motor seeing no current by using the series/parallel contactors already in place to kill it.


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## major (Apr 4, 2008)

booksix said:


> As for dual motor reverse in series, wouldn't that only limit to speed (already way to fast for reversing) due to half voltage? Because it's much cheaper to run only one reversing contactor and have the second motor seeing no current by using the series/parallel contactors already in place to kill it.


Yeah, but if you needed reverse torque for getting up hills backwards, the series arrangement would give you twice the torque for a given current. So, keeping volts, amps and RPM low, but having force to get it up. If you don't need it, forgetaboutit.

major


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## booksix (Aug 26, 2008)

ahh, I gotcha! Didn't think of needing the torque... Now I wonder; will a single GE 9" (hyster lift) be ok on it's own to reverse the car (3500#s)?


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