PDA

View Full Version : Wiring diagram - seeking comments



Lunchbag
30 November 2014, 2016
Attached, I hope, is my wiring diagram. If you have time to examine and comment on it, I would greatly appreciate it. Thanks!
6097

furyphoto
04 December 2014, 2311
Looks OK,

Are you using a 12v relay that can handle the whole pack voltage on the contact side? If your relay arcs closed, you have no way to turn off the high voltage systems. I actually switched to a 12v coil contactor to avoid having to use the pack voltage to close the contactor.

Is the squiggly symbol on the - side of your pack a shunt for the Cycle Analyst? That's what I'm assuming.

Lunchbag
06 December 2014, 1358
Are you using a 12v relay that can handle the whole pack voltage on the contact side?

I haven't bought the relay yet, but yes, I'm looking for something rated for 90+ VDC. Anyone with a recommendation for this part (and vendor), please let me know.


If your relay arcs closed, you have no way to turn off the high voltage systems.

I'm hoping the proper contact rating and small load will make that unlikely, but I get the point. Maybe I should consider disconnect switches on both the high-voltage, low-current loop and the high-voltage, high-current loop, in case either the relay or contactor sticks closed. On the other hand, the failure of either the relay or contactor in itself should be non-catastrophic...the only problem would be, I couldn't turn the drive system off until I pulled a fuse and replaced the broken component.


I actually switched to a 12v coil contactor to avoid having to use the pack voltage to close the contactor.

I thought about that, but the AXE operator's manual says the contactor's coil voltage should also be rated for the pack voltage. I don't know why it says that, but I got a 72V coil just in case.


Is the squiggly symbol on the - side of your pack a shunt for the Cycle Analyst?

Yes, it's the 0.25 mOhm shunt. Thank you for the comments!

frodus
06 December 2014, 2345
The coil voltage can be whatever you want it to be. The contact voltage on the contactor should be rated for higher than pack voltage. Making the coil voltage 12v makes it easier to switch wince you likely have 12v anyway

For the ksi, the Tyco kuep series is good. Forget the model but it has 150vdc contacts and a 12v coil.

Lunchbag
12 December 2014, 1733
Thanks Travis, I got a KUEP-3D15-12 on Ebay for $15 shipped. Does this relay need a flyback diode on the coil?

frodus
12 December 2014, 1859
Well depends on what you're hooking it to. If you're controlling with a FET then yes you need one. If it's just a switch them you may be able to get away without it. Generally speaking when you have any kind of coil that doesn't have a diode or circuit on it, you should have a diode there to give the current a path when you open the Circuit. Your call.