I Need a Switch for My Voltage Converter

[B Swan]

Hello. I searched the forums for an answer already, not wanting to repeat a question unnecessarily. But I haven’t yet found quite the answer I’m looking for.

I’m getting a voltage converter for my 94 Marathon, 36v to 12v 20amps. I’m not too keen on wiring it to the key switch. I will if it comes to that, but I hope not to have to. I just want to be able to disconnect the converter when I charge my cart. So, until I find a more suitable solution, I may just use spade connectors on the input cables to disconnect them before charging.

In any case, what size switch do I need? I know a 12v switch is too small - I just read someone else’s thread, “12v or 36v toggle.” I also remember reading that amps play a big part too. So, and trying to keep the hook up as simple as possible, what size switch in volts and amps do I need? I’d like not use a relay if that’s at all possible. But if not, then what size relay do I need? And can it be one of the simpler looking relays? You know, the relays that look like a big fuse holder. NOT one of the relays that look like a fuse box!

Thanks for any help! (And also, thanks for what I’ve learned already from this forum!)

Also, if it makes a difference, I’m not restoring it. I’m just having fun will I save to purchase a newer model cart.

[B Swan]

Just in case my title caused confusion, I’m not looking to see if someone here is selling a switch. I need to know how many amps and volts a switch needs to work safely. Even if I purchase a converter with the 5th ‘trigger’ wire, I’d still like prefer to use a separate switch. I imagine a trigger wire switch wouldn’t need as many amps or volts as a switch on the +input cable. Though I could be wrong. Any help would be greatly appreciated.

Thanks

[Signal_Engineer]

20 amps at 12 volts is 240 watts (P=IV), and 240 watts at 36 volts is 6.67 amps (I=P/V), but the convertor is not 100% efficient so the main input current at full load output will be a little more, therefore you need a switch that can handle about 10 amps DC, just to be on the safe side. Remember it is much harder for a switch to break a DC current than it is to break an AC current, so make sure that the switch is rated for DC amps.

The current flowing through the control or switch wire of the convertor will be very small, so switch rating is not such an issue here.

Hope that helps.

[meimk]

How about a later version EZGO 4 terminal key switch? Fits the same hole, uses the same key, has: off / run / run with lights positions.
http://www.cartpartsplus.com/ezgo-sw...ition%20switch
Yes you could use a separate switch, but then you would need always remember to switch on off independent of the key. With one of these you could run the 5th control wire through what would normally be the headlight switch and it would give you the ability to turn the converter on & off at will, while knowing it is absolutely off any time the key is off.

[Sir Nuke]

Originally Posted by B Swan

Hello. I searched the forums for an answer already, not wanting to repeat a question unnecessarily. But I haven’t yet found quite the answer I’m looking for.

I’m getting a voltage converter for my 94 Marathon, 36v to 12v 20amps. I’m not too keen on wiring it to the key switch. I will if it comes to that, but I hope not to have to. I just want to be able to disconnect the converter when I charge my cart. So, until I find a more suitable solution, I may just use spade connectors on the input cables to disconnect them before charging.

In any case, what size switch do I need? I know a 12v switch is too small - I just read someone else’s thread, “12v or 36v toggle.” I also remember reading that amps play a big part too. So, and trying to keep the hook up as simple as possible, what size switch in volts and amps do I need? I’d like not use a relay if that’s at all possible. But if not, then what size relay do I need? And can it be one of the simpler looking relays? You know, the relays that look like a big fuse holder. NOT one of the relays that look like a fuse box!

Thanks for any help! (And also, thanks for what I’ve learned already from this forum!)

Also, if it makes a difference, I’m not restoring it. I’m just having fun will I save to purchase a newer model cart.

B SWAN I did this very thing years ago and its STILL hooked up this way and worked like a champ.....I connected the input DIRECTLY across the pack....then on one leg if it I put a TOGGLE and located it close to the F&R selector (I have a series cart so its by my right knee) and my converter and fuse box is under the seat, so it was coinvent.

[Signal_Engineer]

Originally Posted by B Swan

Hello. I searched the forums for an answer already, not wanting to repeat a question unnecessarily. But I haven’t yet found quite the answer I’m looking for.

I’m getting a voltage converter for my 94 Marathon, 36v to 12v 20amps. I’m not too keen on wiring it to the key switch. I will if it comes to that, but I hope not to have to. I just want to be able to disconnect the converter when I charge my cart. So, until I find a more suitable solution, I may just use spade connectors on the input cables to disconnect them before charging.

In any case, what size switch do I need? I know a 12v switch is too small - I just read someone else’s thread, “12v or 36v toggle.” I also remember reading that amps play a big part too. So, and trying to keep the hook up as simple as possible, what size switch in volts and amps do I need? I’d like not use a relay if that’s at all possible. But if not, then what size relay do I need? And can it be one of the simpler looking relays? You know, the relays that look like a big fuse holder. NOT one of the relays that look like a fuse box!

Thanks for any help! (And also, thanks for what I’ve learned already from this forum!)

Also, if it makes a difference, I’m not restoring it. I’m just having fun will I save to purchase a newer model cart.

If you intend to connect the convertor direct to the main battery pack (via a 7.5A or 10A fuse) and a switch, then you don't need a relay.

The relay is only necessary if you were thinking of connecting the convertor to the same terminal as the B+ supply to the controller, i.e. on the output side of the solenoid. There can be problems when the capacitors inside the convertor discharge back through the controller after it has switched off the solenoid, since the controller thinks it has already switched off the solenoid, resulting in 'no go' issues. Using a relay to feed the convertor avoids this issue.

I'm not sure what type of controller / drive system your cart will have, so the information above may or may not apply to your situation. Others on the forum will know better what applies to your type of drive system.

[B Swan]

Thanks Guys!

I think I read a post where you talk about that, Sir Nuke. But I wasn’t clear on the switch rating that Engineer mentions.

It’s a 94 Marathon with rotary coil assembly speed control. I’d like to get a new key switch, especially one with unique keys. But any time I think about it, all that comes to mind are the 3 days it took to replace cables from the motor to the resistor and from the resistor to the speed contacts. I hadn’t known until then that nuts and bolts can rust together. I got more stories but suffice it to say I have 0 interest in fooling around with any more old parts.

So, for sure, I’m going with Sir Nukes set up. I decided on a converter with the key switch wire. What I’m still confused about is how to power the switch. If I use two batteries (for + and -), that defeats the purpose of having a converter, right? If I use the main positive, do I then need a switch rated for 36v dc? (And while we’re on the topic, I understand 36v dc and 36v ac, but exactly how does 36v ac/dc work?) Or do I look a for switch rated for 10amps regardless of voltage? I wouldn’t power the switch from the accessory side, would I? I’m no electrician, but that doesn’t seem like the circuitry I should be going for.

Again, thanks! You don’t know how much this helps! 😅 I can’t risk the whole debacle I mentioned earlier. Folks, it included a power cutter. I just can’t.

[B Swan]

I read your posts again. PLEASE correct me if I’m wrong, but so long as the switch is rated for 10 amps dc, it should work? No blow ups or melted battery posts?

[B Swan]

Okay, so which wire diagram is accurate, A (top left) or B (bottom right)? And what switch rating do I need? I’ve read through more posts but still don’t feel confident enough to plug things up. I read through Cohen’s post, but still have a few questions.

Is it still possible to turn the converter off? My concern is charging while the converter is on. If so, I just may go his route and call it a day.

Except, I don’t even want to tap into the current +key switch wire.
17295EB2-BC03-4782-81FB-8F22D1390047.jpg

So which diagram and what rating. Yes, I can be painfully dense at times. So thanks for your patience and help.

[DB Cooper]

This is what I used:
https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1

125V, more than enough