Voltage reducer on a switch - 12v or 36v switch? Other ideas?

[bigbluesd]

I know enough about electricity to be dangerous -- literally dangerous, so please bear with me and correct me if anything I say is really stupid.

I bought a TecScan VOLTSeasy 240 watt (20 amp) voltage reducer to run all of my accessories off of on my 36v cart. When you connect the reducer to the batteries there's a huge (like real huge, much bigger than what you would see on a car battery) spark. Maybe I'm a sissy or maybe I've seen too many battery explosions but I'm not real fond of big sparks close to lead acid batteries, especially when it's inside my garage. Plus I don't exactly trust these chinese electronics and would like to be able to disconnect the voltage reducer (and subsequently all accessories) quickly and easily in the event of an issue.

So I wired the red/positive input lead (to battery) to a 12v automotive switch that I had lying around (and from there to the positive side of battery chain). The black/negative lead goes straight to the negative side of my battery chain.

The wiring itself is absolutely correct, I can say that with certainty, so it's not a wiring issue that I'm about to describe.

I powered it all up using the switch and everything worked beautifully for a few minutes. I kept turning it all on and off and testing voltage at my fuse box and negative buss for each accessory and everything worked great until it just didn't. The LED on the switch for the voltage reducer didn't light up, the green light on the reducer itself didn't light up and I had no voltage at the fuse box and buss.

I figured either the reducer or the switch had died. I tested the reducer by taking the leads off of the switch and touching the positive leads together and got that huge spark (big enough to melt the connectors where it touched ). I figured that meant that the switch must be bad but when I test it with a continuity test on my multimeter I get the beep when the switch is turned on.

So now I'm really confused...

If the issue is with the voltage reducer not putting out power (on the output), that shouldn't affect the LED on the switch not working all of a sudden (because the LED is connected directly to the battery positive and negative - although it's getting 36v instead of the 12v that it's designed for).

If the issue is with the switch itself, why would it test correctly for continuity? And if the problem is just that I've blown the LED in the switch, why wouldn't I get 12v voltage at the buss still? And why wouldn't reducer have the green light (that shows correct voltage) when turned on?

Does it matter that I used a 12v switch on a 36v circuit? Assuming that the 240 watt reducer pulls 6.7 amps on a 36v system (shouldn't this be the case?) it doesn't seem like a ridiculous current and most identical switches that I see online are rated for 15 amps. Do I specifically need a 36v switch or is it the amperage that really matters?

I'm considering installing a battery disconnect switch on that circuit instead of a 12v switch but that seems overkill and since they are not sealed (like a 12v switch) I'm a little concerned about sparking in the battery compartment with that as well, am I worrying too much?

I know you guys can't solve my problem from what I'm describing here but I'm mainly just looking for any ideas or similar experiences that might help me figure this out. Thanks!


Now I'm just confused.

[cgtech]

1- if you "don't trust Chinese electronics", why you risk it then?

2- the huge spark is the "inrush current", it's very high, and fried your switch. The "under load" current isn't high, but the "fill the capacitors" current is near infinity (as much as the board traces & capacitor leads can pass).

[Cobra,1]

Been there done that.
The amp draw of a 36 volt battery pack is to great for low amp 12 volt switch.
Either add 36 volt relay( about 12 bucks)relay use’s toggle switch to power relay rated for hi amps to connect convertor to batteries so not to fry toggle switch. or get convertor with trigger/signal wire that uses low voltage from key switch to turn on convertor.
I used relay opposed to buying new converter.

Convertor typically only draw 1 or less amp when not in use but they do draw off batteries if sat unused for long periods so figure that in your charging schedule.

I can’t notice battery discharge rate over weeks with convertor on or off so it’s not loosing sleep over lol😊