72VDC to 12VDC Reducer

[ScottA58]

I have a 72V cart and I am adding a few accessories, (Roof LED light bar, green front LED light bar, 2 rear cube LED backup lights, horn). Each accessory will be on individual fused circuits with relays. I purchased a Holdwell 72VDC to 12VDC voltage reducer from Amazon. It was advertised as an EZ-GO part. There are 4 wires coming out it Red, Black, Green Yellow. The label on the end indicates that the input wires are Red & Black, and the output wires are Green & Black. Apparently the input & output share the common Black ground wire. The 4th wire is Yellow. The label indicates this is the Control wire. Based on other voltage reducers I have used, I assume this is the wire that turns the output on or off and should be connected to 12VDC keyswitched power. Can any one verify the yellow should be connected to 12VDC keyswitched power?

[Cobra,1]

No experience with that reducer. But could you not use temp “alligator clips” connection to battery,no load on out put wires and test with volt meter on 12 volt output wires to test if 12 volt present once you touch yellow wire to positive post?
That should prove if yellow wire is control/ switched wire.

[Mooncarter]

Where are you getting the 12v at the switch from?

[orangeman6]

Isn’t the control wire (on/off) usually rated at the same voltage as the input? I know mine is. Seems pointless to have to get 12v before I have 12v.

[bobbycason]

Originally Posted by orangeman6

Isn’t the control wire (on/off) usually rated at the same voltage as the input? I know mine is. Seems pointless to have to get 12v before I have 12v.

In wiring size it's no so much the voltage but the amperage passing through that matters.

With my cart I replaced the key switch with a rocker switch from autozone. I made a pigtail for the control wire for my reducer so when I turn the cart on the reducer comes on.

[yurtle]

I think both comments are related to "pack voltage" vs. the stated "12 volts" at switch. Perhaps OP misspoke and meant pack voltage when he said 12 volts?

[orangeman6]

Originally Posted by yurtle

I think both comments are related to "pack voltage" vs. the stated "12 volts" at switch. Perhaps OP misspoke and meant pack voltage when he said 12 volts?

Yes. My point was whether 12v would turn on the reducer, or 72v. It would make sense that the trigger wire was the same as pack voltage. The trigger wire doesn’t carry any real amperage.

[yurtle]

Yep. My trigger was 48 volts, when I had a reducer. I fed it from the second switch on a three position key switch.

[ScottA58]

I have verified that on my 48V cart I have the Madjax 48V-12V 30A reducer. The trigger on that reducer is 12VDC from the key switch. When I install this new reducer in my 72V cart, I may try 12V for the trigger first.

[Mooncarter]

How does the key switch get 12v when the reducer is off?