looking for a battery power switch

[izeman]

ps: i'm really looking forward to see this massproduced. i'll be your first customer!

And I'll be the second.

I mentioned to methods that he should add these to his product line but he didn't show too much interest. I think his plate is about full these days.

If you need one, and can't solder one yourself just pm me. I think I can help.

 

[mvly]

izeman,
I understand you are looking for brand of switch, capable to switch your motor current.
So staying on topic :
I can suggest NKK switches sold by Mouser or DigyKey,
I extensively used them on my conversions.
You cannot beat them for quality MadeInJapan.
http://www.alliedelec.com/search/productview.aspx?SKU=70192243

If you check out the specs for the switch it states 1A for 125V DC. It is AC when you get 50A. For the most part you would be fine. Just want to mention it to you if you find your switch blown one day of hard riding. : )

 

[miro13car]

Wrong
It is rated 50A at 30V
NKK data sheet
Just Google NKK

Of course manufacturer would NOT print all specs on the switch

 

[nicobie]

Wrong
It is rated at 50A at 30V
NKK data sheet

I can guarantee that the contacts on that switch will weld shut running 99v when switched on without using a proper sized pre-charge resistor. I tried 2 different ones and cooked both even when using a 1000 ohm resistor. They probably would have worked OK with a 300 ohm one but I wouldn't trust it to open when under load.

This will work but it might be pricey. Luke (LFP) uses something similar on his 'death bike'.

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

 

[miro13car]

Of course spark is produced by charging capacitors when you turn system ON
Maybe your motor controller has higher capacity caps producing such spark
Not on mine for sureI
I am on 36v
I am not worry even for 48v
I do not need crazy voltages to reach 30mph on regular bases
Ask me what system can do it on just 36V
Nothing is going to weld
I have been switching on and off for more than 100 times

 

[_Chris_]

I dont know if it helps you guys any but on my 24 V battery on my 500 W motor I used a normal residential switchboard circuit breaker because they handle switching current really well. I just used a 25 amp one so if the motor drew too much it would protect it and the battery. It will cost you 10 bucks and last you years. You can get double pole ones as well.

I did that because the supplied switch was getting hot and not allowing enough current when I first made the bike.

 

[izeman]

i wanted to test my battery today, and connected the controller with the fet-switch in between.
i had a big spark and was wondering, as the positive supply wire was not connected.
i disconnected everything and measured resistance between the two pins of the fet. and all 3 are 0 ohm.
how can that happen? i used the switch once. worked w/o problems. now it ain't work.
what should i do?

 

[michaeldanger909]

why would one of these not work? just curious

http://www.odysseybatteries.com/images/hellalg.jpg

 

[izeman]

why would one of these not work? just curious

http://www.odysseybatteries.com/images/hellalg.jpg

it will work. but not for very much long maybe. the lower the voltage the longer it will work. the higher the voltage, and the bigger the controller (caps inside) the bigger the sparks will be. and these sparks will destroy the contacts over time.
i connected the controller to the battery last time (80v) and the spark was that big, that i thought there was a short in the controller. but i was always the same.