I have a sabertooth 2x32 motor controller controlling two wheelchair motors, but I’d like to make a battery disconnect of some kind so that I dont need to see large sparks every time I want to connect my sabertooth to the batteries. Also, a switch would be alot easier than screwing and unscrewing a wire all the time.
What’s your suggestions on a means to disconnect the circuit?
I’m using two 12v 30A SLA batteries in series
there are no cheap 24v 30A DC toggle switches that exist,
Could I implement a 24V relay with a basic toggle switch to disconnect the circuit? I dont think this would fix much because the same voltage and amperage would be going though the switch, causing the arcing and melting the switch.
…or would it work?
how do I set up a means of disconnecting my circuit with a 5$ 10A toggle switch that I have? or do I need an expensive special switch of some kind? thanks!
I honestly cannot find any 24v 30 amp toggle switches, not even on Amazon.ca or easy! I can find 30 amp 12v switches though. But it says only 20 A @24v ):
I do own a 20A 12v switch but I fear it will melt when I use it in my circuit later on.
You need to do some research on how relays work and the role of a switch to activate the relay.
The control switch only carries enough current to activate (energize) the relay coil.
Here are some of the basics:
NOTE safety & controls like these & the relay are always put in the + voltage line
= NOT in the ground line.
Also for safety, when actually connecting to your batteries,
one makes the ground or -V connection to the battery LAST
= AFTER all the +V connections have been made. For taking your system apart, this process is reversed = Disconnect the ground(s) first !!
Put an appropriately sized fuse or circuit breaker in the wire from your battery to the Sabertooth.
This safety feature is not an option
Pick the amperage to match the max safe current for your device or a bit above the peak current
you’re going to be operating with, if that is less than the max current of your Sabertooth.
After that you wire in your power control relay. That’s the 30 Amp relay you’ve mentioned.
Your relay Needs to be appropriately rated for your DC current,DC voltage rating & continuous operation.
A simple Normally Open DC relay is all you need.
(Though often it is easier to find 3 power terminal relays which will also work for this.).
But the relay must be rated appropriately to assure it will break (open) at the max current & voltage
at which you will be using it. You also want a relay protected by a case = the relay contacts are not exposed.
You need for this is a SPST relay
= No power applied to the relay coil NO contacts are open -not connected
= power applied to the relay coil and the NO contacts close power is connected to the Sabertooth
This would be a single pole single throw relay SPST.
Then connect NO (Normally Open) terminal of the relay get connected to your SaberTooth main power in connector.
The relay main terminal connects to the output from your fuse or circuit breaker.
If there are three relay contacts, the NC (Normally Closed terminal is not used for this application.
Now for controlling the relay: To manually control the relay a switch will work just fine. Yep also SPST.
The switch for a simple manual control It ONLY carries the current needed to activate the relay coil.
It does NOT carry the full Sabertooth operating current.
The relay coil is designed to match the relay control voltage.
The switch connects the relay coil to +v and the other relay coil terminal is connected to the -V or ground.
The current thru the coil is a small current and most likely any automotive SPST toggle switch will work
even a 5 amp switch is likely overkill.
Frappim, I hope I covered enough in this to be of some help for your project.
