On off switch for Pie III

[Waldmeister]

Hey guys, yet another newbie question:
My battery (48V connected via Anderson plugs) doesn't have a switch, so I need to disconnect it each time I want to switch off the pie. Having read this post http://goldenmotor.com/SMF/index.php?topic=4340.0 didn't really help me.
I don't even need a key switch, a regular on off solution would do. What do I need to take into consideration? Has anyone found an easy solution? Would such a thingi help?

http://www.mercateo.com/p/live~s.10!showGrossColumn*102-703195%282d%29BP/Kraus_Naimer_Ausschalter_10_A_CG4_CG4_A200_600_FS2_1_x_60_.html

Thanks for your help!

[truly_bent]

This keyswitch (http://www.goldenmotor.ca/keyswitch/), found on Gary's site, would probably do.

Have you fused the battery? Generally recommended. Not sure the BMS is up to handling a dead short and your battery is a sizable investment. I'm considering using one of these marine breakers: http://tinyurl.com/9gob88t. It handles fusing and allows manual line breaks in one. No keyswitch though.

For more info see attached data sheet (breakers on the last page).

[Waldmeister]

  Thanks man, that's some useful information there. Gary doesn't seem to sell the switches anymore. I'm gonna try to find marine breakers over here in Germany since I haven't fused the battery so far. Seems to be a good solution.

[Waldmeister]

Ok I'm even considering ordering from U.S. since I need new Anderson connectors anyway and shipping isn't any more expensive than the difference I'd have to pay for them over here. ... I assume I'd have to interrupt the (-) with the breaker? Or do I use both lines ?
Thanks again for your much appreciated help!

[truly_bent]

Generally, the positive (+) line is interrupted with a fuse. I think this originated from the practice of grounding automotive frames to the negative (-). In a "floating" (not grounded) system, I suppose it doesn't matter, technically speaking, but why not stick to convention?

[Waldmeister]

Hey, thanks!
I finally got a 48V 50A thermal circuit breaker. So I will run the red cable through the circuit breaker and bypass the black cable (which I will have to connect with a single pole Anderson (I have a 75A one in stock)). Will that work?  Is 50A enough? (I'm rather a fat... and on my way to work there's a steep hill, but the PIE has never shut off so far and never gotten excessively hot). Sorry if I'm being overcautious with all my newbie questions. Just makin' sure... Hope nobody is getting a headache because of all the heads that must be shaking at such questions. Anyhow.... thanks for your help, folks!
By the way, I'm using a MP5 now with my old lifepo4 48V 15ah ..... been plugging and unplugging that old MP3 for quite a while, but I guess its time for a better solution now.

[Bikemad]

A 50 Amp circuit breaker should be fine for the MP5 as it should only draw a maximum current of around 30 Amps.

Alan
 

[Waldmeister]

Thanks, Alan!