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Electronics => Electronics => Topic started by: TaoBaiBai on September 08, 2012, 12:20:53 AM

Title: High Current Switch
Post by: TaoBaiBai on September 08, 2012, 12:20:53 AM
Hi all,

How to switch a lipo battery and a 60A motor?
The switch can be as small and light as possible.

Title: Re: High Current Switch
Post by: Soeren on September 08, 2012, 01:16:54 AM
Hi all,

How to switch a lipo battery and a 60A motor?
The switch can be as small and light as possible.
Do you want to drive the motor with the battery and are asking about a speed controller or what? (That's the only way I can get your post to make sense).
If so, a PWM controller is the ticket.
Title: Re: High Current Switch
Post by: TaoBaiBai on September 08, 2012, 03:44:20 AM
I want to use a switch to on off the battery and the motor can draw 60A current.Can any switch allow 60A current flow through?
Title: Re: High Current Switch
Post by: waltr on September 08, 2012, 08:11:54 AM
Look at automotive switches and relays. Relays since most mechanical switches can not handle 60A. The switch turns on the relay which then turns on the motor.
Title: Re: High Current Switch
Post by: Sylvestre on September 08, 2012, 09:37:53 AM
Also, there are a few high power switches here http://www.robotmarketplace.com/products/power_switches.html (http://www.robotmarketplace.com/products/power_switches.html)
Title: Re: High Current Switch
Post by: knossos on September 08, 2012, 05:28:03 PM
With heatsink, thermal paste, and active cooling the Dagu Wild Thumper High Power Switch can supply 60A continuous and can be switched locally with a small switch on the PCB, remotely with an externally mounted switch, or remotely using a microcontroller digital output.
Title: Re: High Current Switch
Post by: Soeren on September 08, 2012, 07:33:44 PM
Hi,

I want to use a switch to on off the battery and the motor can draw 60A current.Can any switch allow 60A current flow through?
Like waltr, I can recommend automotive relays like this one
(http://ecx.images-amazon.com/images/I/41PKT0qfC0L._SL500_AA300_.jpg) (http://www.amazon.com/Power-Relay-Single-Double-Throw/dp/B001PNMBE4)
(check your local gas tank or a shop selling car acessories, they'd likely be cheaper and you won't have to pay shipping).
It depends on your battery voltage, of course, but automotive relays can be found in 6V, 12V and 24V and like you can see on this page (http://www.hascorelays.com/electro_80_amp_car_series.asp), the coil in the relay can be energiced with a voltage within a range (for this particular relay) of:
( 6V)  4.2V-7.8V
(12V)  8.4V-15.6
(24V) 16.8V-31.2V

Another option is to make a knife switch yourself out of bronze or brass, if you have the mechanical skills.

The cheapest of all is to just plug out the fuse that you need near the battery anyway, but the socket may deteriorate over time, as they're not made for daily fuse changes.
If you want to go that route, the type to get is the Maxi Blade type (don't confuse them with the smaller versions of blade fuses).
(http://www.thetoolboxshop.com/ekmps/shops/adrcomponents/images/0-377-60-pack-of-2-blue-maxi-blade-fuses-60a-1399-p.jpg) (http://www.thetoolboxshop.com/0-377-60-pack-of-2-blue-maxi-blade-fuses-60a-1399-p.asp)