24V System Question....

As long as the switch is rated to switch at LEAST 24 volts DC, at your rated current (15A), it would be fine. A switch which is rated at 15 amps will work fine at any amperage up to that point. You wouldn't need to get it oversized.

The only time that the current would EVER be that high is if the dc-dc converter output was at max current. Your operational load is going to be in the less-than 100 watts range.

As others have said, add a 15 Amp slow-blow fuse (or breaker) to the feed circuit. A slow-blow fuse handles short-term surge currents that you can experience when the converter starts up without blowing. That way, if you developed a short, the fuse would blow, the feed circuit would be disconnected, and nothing would fry.

And, as far as switch ratings go, that's the current that they are tested to handle correctly over thousands of on-off cycles. In an emergency, they can handle more current that that. (at higher than rated currents, switches can experience 'erosion' of the contact faces. One or twice at double the current shouldn't destroy the switch - but, it will shorten its life somewhat. If you repeatedly exceed the current rating, it would lead to a short switch life, though)

All fine and good, however, the switch is not going on a 15a line... It's going on a 30a+ line. I already have a switch after the DC-DC converter for the 12v stuff, it's the 24v 30a line going to the controller that I need a switch for.

The REAL problem I'm having is finding ANYWHERE that has any kind of selection of 24v switches. (I want a switch to turn on/off, not a relay.)
 
I think the switch only has to handle the amperes going through it. If your DC-DC converter only draws 15 or less Amps you can use a 15A switch. You would only need a larger switch if for some reason you wanted to add a switch in between your battery and motor controller. It shouldn't matter if your batteries can supply 40a as long as that amperage isn't traveling through the circuit with the switch on it.
 
I think the switch only has to handle the amperes going through it. If your DC-DC converter only draws 15 or less Amps you can use a 15A switch. You would only need a larger switch if for some reason you wanted to add a switch in between your battery and motor controller. It shouldn't matter if your batteries can supply 40a as long as that amperage isn't traveling through the circuit with the switch on it.

But wouldn't the amperage be pulled through the switch (between the controller and the battery) while I'm riding the bike?

More on that in a minute, but first...
Why does everyone want to talk about the DC-DC converter? Has NOTHING to do with it!

I must not be explaining it correctly.....

This has NOTHING to do with the Converter. I want a switch that is between the Battery and the controller.

I have it set up like this....

Battery with two sets of power (+ and -) wires... first set goes to controller, second set goes to the DC-DC converter, after the DC-DC converter is a switch, to switch off the 12v accessories (when I'm inside a store or otherwise not home, nor riding the bike, or when I'm charging the battery) so the converter part is fine.

I want a 24v 30a switch between the battery and the controller. I want it illuminated. The same wires that supply power to the controller, are the same wires I (have to) use to charge the battery. I want to add a THIRD set of wires (to the two that are already there) and add a charger port, but I want the switch (in between the battery and the controller) to disconnect the controller when I go to charge the Battery. (and since it just happens to be there, disconnect the converter, but it's NOT necessary, so please no more suggestions about the damb DC-DC converter :))

Now another question(s) come into play...
What size (awg) wires should I have going from the battery to the switch, from the switch to the controller and from the controller to the 12v accessories.
And for the "more on that in a minute part"....
The other question is, if my bike is running, and I have a switch there (in the ON/Closed position) does the amp rating on the switch have ANY effect or disadvantage for the amps the controller will be pulling? My motor (on my 200lb+ bike) is a 250watt 24v motor, the battery is a 24v 30ah battery and is capable of 40a continuous / 60a peak draw, but I doubt the controller pulls any more than 30a from that low wattage/voltage motor. (I don't know what the controller pulls or is able to pull, but I was guessing that it would be somewhere close to (given the motor's rating) about 15a continuous and 25a max, hence for the desire to have an Illuminated 24v 30a Rocker On/Off Switch.) Anyone know where I can find one?
 
If you look around long enough at Amazon.com,you can find a 24V, 30A.dc switch,I did.It did take some digging,their categories are kind of screwed up.I'm not sure if it was illuminated.
 
If you look around long enough at Amazon.com,you can find a 24V, 30A.dc switch,I did.It did take some digging,their categories are kind of screwed up.I'm not sure if it was illuminated.

If you found it on Amazon, could you look through your browser history and see if you can find it again and then send me the link?
 
I'll try tomorrow,& let you know,it was rather convoluted,I got there in Amazon,via a link from Google.But when you tried A directly it was pretty hard to find,I remember now.
 
I have looked around some more and have found a site that should be right up your alley.You can get to it via Amazon "home improvement"(hard),and I don't know if they sell all their stuff via A.You'd be probably better off going to their site directly:
www.delcity.net and look under their product categories for "switches" ,then look for battery&ignition switches.I think you should also look under circuit breakers,some can be disconnected, like your house panel breakers.I think a breaker is nice to have in order to keep from overloading your controller/motor.BTW their search engine stinks.Good luck
 
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I have looked around some more and have found a site that should be right up your alley.You can get to it via Amazon "home improvement"(hard),and I don't know if they sell all their stuff via A.You'd be probably better off going to their site directly:
www.delcity.net and look under their product categories for "switches" ,then look for battery&ignition switches.I think you should also look under circuit breakers,some can be disconnected, like your house panel breakers.I think a breaker is nice to have in order to keep from overloading your controller/motor.BTW their search engine stinks.Good luck


Thank you for the website and your time. However, they don't have rocker switches that are rated for 24v 30a or higher, actually they don't even have anything rated over 15a. :(

I think I'm just going to give up on this. NO ONE makes a rocker switch (illuminated or not) that is rated for 24v DC 30a or higher. :(

I think I'm just going to go with a "Battery Switch". I'm going to have to just give up on the illuminated switch idea and go with something more practical.

Oh well.
 
You could also try Marine places, I know for sure that they sell 24 volt switches for the bilge pumps.
Also Golf carts use a small box to reduce the volts to 12, try ebay or golf cart sites
 
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