High Current Switches...

[Botvink]

Hello friends,

I am curious that what switches you are using at projects, I will use it for 150A peak 40-50A continous current needed motor driving system.

At digikey most switches are mostly 20A rated..

https://www.digikey.com/en/products/detail/nkk-switches/S31-CUL-WL/13548176

https://www.digikey.com/en/products/detail/apem-inc/637H-2/1280285

What should I use?

 

[harrisonpatm]

Hello friends,

I am curious that what switches you are using at projects, I will use it for 150A peak 40-50A continous current needed motor driving system.

At digikey most switches are mostly 20A rated..

https://www.digikey.com/en/products/detail/nkk-switches/S31-CUL-WL/13548176

https://www.digikey.com/en/products/detail/apem-inc/637H-2/1280285

What should I use?

For 150A you need a large connector, a contactor/relay, and/or a heavy duty circuit breaker. There are no small toggle switches of any kind that can handle 150A.

 

[chuyskywalker]

Agreed; the best I ever found was a medium size toggle that could handle 40A DC.

 

[harrisonpatm]

You could also search for "battery disconnect" switches, if you'd like. They're going to be big and bulky, and you can usually only use them on lower voltage, sub 60Vish. But maybe you'll see one that's manageable for your use.

 

[fechter]

The circuit breaker on a Sur-ron is pretty nice. I run peaks of 180A and it has never tripped. They seem to handle the inrush current of charging the caps inside the controller without a pre-charge circuit.

 

[Botvink]

You could also search for "battery disconnect" switches, if you'd like. They're going to be big and bulky, and you can usually only use them on lower voltage, sub 60Vish. But maybe you'll see one that's manageable for your use.

Thanks! This type I am finding, I will measure it's resistance..
I don't know why companies not making miniature type high current switches... It may be machined with different designs... :/

 

[Hummina Shadeeba]

A loopkey with these antispark connectors has got to be the simplest:

Custom QS8 and QS10 antispark plugs with high resistors for high voltage antispark on/off loopkey

Custom made by the manufacturer. Higher resistors put in for higher voltage. Xt90s have much lower resistance and the antispark breaks especially with higher voltage and more inrush current 10$ each Makes a good loopkey

endless-sphere.com

 

[harrisonpatm]

I don't know why companies not making miniature type high current switches... It may be machined with different designs... :/

High current means thick conductor. Which means more mass, aka bigger and heavier. It's just not physically possible to have something finger-sized that easily toggles a couple hundred amps.

Thanks! This type I am finding, I will measure it's resistance..

Can you confirm which voltage you are using? I have used that switch, and it does not reliably cutoff anything over 60v.

 

[4πr^2]

I don't know why companies not making miniature type high current switches...

They do. Search IGBT or MOSFET. 200V, 200A in a package about the footprint of a postage stamp would not be uncommon.

 

[nicobie]

The circuit breaker on a Sur-ron is pretty nice. I run peaks of 180A and it has never tripped. They seem to handle the inrush current of charging the caps inside the controller without a pre-charge circuit.

View attachment 337103

I wish I would have known about these 10 years ago. Would have saved me a lot of time, money and headaches.

 

[Comrade]

Hello friends,

I am curious that what switches you are using at projects, I will use it for 150A peak 40-50A continous current needed motor driving system.

At digikey most switches are mostly 20A rated..

https://www.digikey.com/en/products/detail/nkk-switches/S31-CUL-WL/13548176

https://www.digikey.com/en/products/detail/apem-inc/637H-2/1280285

What should I use?

 

[Hummina Shadeeba]

Without an anti-spark as part of the switch I believe you will be greatly stressing the capacitors on the esc with the inrush current.

 

[nicobie]

Without an anti-spark as part of the switch I believe you will be greatly stressing the capacitors on the esc with the inrush current.

That is so true and was the real reason I was having so much trouble. I was running 24 S (100V) at the time.

 

[Hummina Shadeeba]

That is so true and was the real reason I was having so much trouble. I was running 24 S (100V) at the time.

Breaking escs?
I hear it’s common to blow the capacitors without a decent antispark and not know it and then the esc breaks

Someone did the math on the forum revealing how much current the caps are hit with even with some of the dinky antispark plugs generally for sale and their resistance is much too low for the voltage we use and esc’s typical capacitance and there’s a big inrush current (they get warm). That’s why I had those custom QS8 and QS10 plugs made. Get some!! They’re almost my cost and they solve the issue simply and loopkeys have lots of benefits as well. I had to get a bunch made to get them to make them and I have way too many.

 

[nicobie]

No, I kept welding switches/relays open.