looking for a battery power switch

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izeman   10 GW

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Re: AW: looking for a battery power switch

Post by izeman » Jan 01 2013 6:16pm

nicobie wrote:
izeman wrote:
ps: i'm really looking forward to see this massproduced. i'll be your first customer! :)
And I'll be the second. :mrgreen:

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   10 kW

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Re: looking for a battery power switch

Post by mvly » Jan 03 2013 10:24pm

miro13car wrote: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/produc ... U=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   1 MW

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Re: looking for a battery power switch

Post by miro13car » Jan 04 2013 1:47pm

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

Of course manufacturer would NOT print all specs on the switch
Last edited by miro13car on Jan 04 2013 2:05pm, edited 1 time in total.

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nicobie   10 MW

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Re: looking for a battery power switch

Post by nicobie » Jan 04 2013 2:02pm

miro13car wrote: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
Image

May your tote always stay tight and your edge eversharp :wink:

my eTownie build thread: http://endless-sphere.com/forums/viewto ... =6&t=23701

miro13car   1 MW

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Re: looking for a battery power switch

Post by miro13car » Jan 04 2013 2:12pm

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

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_Chris_   100 W

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Re: looking for a battery power switch

Post by _Chris_ » Jan 06 2013 6:24am

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.
The original bicycle was created without a motor, but we can fix that!

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izeman   10 GW

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Re: looking for a battery power switch

Post by izeman » Jan 16 2013 4:30pm

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   10 µW

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Re: looking for a battery power switch

Post by michaeldanger909 » Jan 20 2013 5:22pm

why would one of these not work? just curious

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

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izeman   10 GW

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Re: looking for a battery power switch

Post by izeman » Jan 21 2013 3:08am

michaeldanger909 wrote: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.

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