Tried to add converter...almost set my cart on fire

[Fairtax4me]

Isolated Grounding of the input and output circuits really doesn't make that much difference for these. The two negative wires can be tied together if you want to do that. And then they should be connected directly to battery pack main - or B- terminal.
What's very important is that none of your accessories or anything else electrical are grounded to the frame of the cart.
Fire is always a concern due to shorting of the Reducer (which is what happened in this case) which is why you must always use a FUSE on the input side of the reducer!
Fuses are not to protect the device, they protect the Wires from becoming glowing string lights when the device fails or when the wires touch each other inappropriately.

While it's useful to have a fuse block for your accessories, you also need to have a separate fuse and fuse holder for the main input power to the reducer.

Can't really tell much without seeing the setup on your cart, but some things to make sure of... check your fuse block for continuity between the + and - side. Since alot of these newer fuse blocks have + and - terminals on the same block if something is hooked up wrong it will short the block and that can cause your reducer to be shorted and cook.

Another thing, make sure you have a negative wire from your fuse block that goes to the Battery Pack main negative. This wire needs to be the same size or larger than the 12v supply wire from the reducer.

You mentioned the connections you made to the pack and it sounds like you had the Main + and - for the pack disconnected and were going to reconnect those after the reducer wires were connected. That will cause you grief with burned battery terminals.
The largest cables need to be in direct contact with the battery post, so your main + and - for the cart need to be on the battery posts first, and any smaller wires can go on above those. This is important, because you WILL fry battery posts if it's done the other way.

These cheapo reducers will arc when first connected to power. Pre-charging will reduce that, but it's not really necessary. If you use a toggle switch on the input side you don't have to deal with the arc. And then you also have a quick and easy way to shut off power to the reducer if you need to, or when the cart is put into storage to help eliminate extra current draw.

[NinjaPixie]

Originally Posted by Fairtax4me

Isolated Grounding of the input and output circuits really doesn't make that much difference for these. The two negative wires can be tied together if you want to do that. And then they should be connected directly to battery pack main - or B- terminal.
What's very important is that none of your accessories or anything else electrical are grounded to the frame of the cart.
Fire is always a concern due to shorting of the Reducer (which is what happened in this case) which is why you must always use a FUSE on the input side of the reducer!
Fuses are not to protect the device, they protect the Wires from becoming glowing string lights when the device fails or when the wires touch each other inappropriately.

While it's useful to have a fuse block for your accessories, you also need to have a separate fuse and fuse holder for the main input power to the reducer.

Can't really tell much without seeing the setup on your cart, but some things to make sure of... check your fuse block for continuity between the + and - side. Since alot of these newer fuse blocks have + and - terminals on the same block if something is hooked up wrong it will short the block and that can cause your reducer to be shorted and cook.

Another thing, make sure you have a negative wire from your fuse block that goes to the Battery Pack main negative. This wire needs to be the same size or larger than the 12v supply wire from the reducer.

You mentioned the connections you made to the pack and it sounds like you had the Main + and - for the pack disconnected and were going to reconnect those after the reducer wires were connected. That will cause you grief with burned battery terminals.
The largest cables need to be in direct contact with the battery post, so your main + and - for the cart need to be on the battery posts first, and any smaller wires can go on above those. This is important, because you WILL fry battery posts if it's done the other way.

These cheapo reducers will arc when first connected to power. Pre-charging will reduce that, but it's not really necessary. If you use a toggle switch on the input side you don't have to deal with the arc. And then you also have a quick and easy way to shut off power to the reducer if you need to, or when the cart is put into storage to help eliminate extra current draw.

Thanks! That's a lot of good info.
After the discussion about sparking and pre-charging etc, I was trying to figure out how to connect it without causing a spark every time I flip the switch on. Sounds like I need to get a 5-wire reducer, add a switch on the 48v pos side, and a fuse between the switch and reducer (matching amp rating of the reducer, I assume).

My thought with the battery terminal connections was to put the big ring on top to help "hold down" the others, but I see now that's very wrong!

[Fairtax4me]

On the input side you typically only need a 10a fuse. Or you might need to go 15a if its a 30a reducer. The input current is usually less than half of the output current.

[NinjaPixie]

I found an example of a reducer that can be set up as either 4 or 5 wire. I think it helps illustrate the difference between the two.
https://www.amazon.com/dp/B09KZ434MM...v_ov_lig_dp_it




I see there is a bridge between the ACC and input + posts on the 4-wire version, and the ACC post is connected to the key/switch on the 5-wire version. This leads me to believe that the ACC and input + both need to be connected to 48v+ input. So the key/switch is interrupting power supply between battery and reducer.

[jasonojordan]

The 48V to ACC via the jumper is just a "switch that is left on". The ACC terminal needs a 48V reference to turn on the voltage reducer. If it is not present then the reducer will not turn on and reduce the voltage.


Any 5 wire reducer can be run as a 4 wire reducer if +48v pack voltage is sent to both the + supply and the key switch wire. This could be done if you are worried more about losing radio presets then you are about the draw of the converter if everything else was turned of.

Originally Posted by NinjaPixie

I found an example of a reducer that can be set up as either 4 or 5 wire. I think it helps illustrate the difference between the two.
https://www.amazon.com/dp/B09KZ434MM...v_ov_lig_dp_it




I see there is a bridge between the ACC and input + posts on the 4-wire version, and the ACC post is connected to the key/switch on the 5-wire version. This leads me to believe that the ACC and input + both need to be connected to 48v+ input. So the key/switch is interrupting power supply between battery and reducer.

[NinjaPixie]

Based on feedback, this is my updated plan for wiring.


New reducer (ProChaser) should be here tomorrow, so hopefully I can get this knocked out this weekend!

[jasonojordan]

Originally Posted by NinjaPixie

Based on feedback, this is my updated plan for wiring.


New reducer (ProChaser) should be here tomorrow, so hopefully I can get this knocked out this weekend!

You would need to do some testing but I think the inline fuses are redundant since there are already two fuses on the reducer already. If the reducer pictured is the one you are getting.

[NinjaPixie]

Originally Posted by jasonojordan

You would need to do some testing but I think the inline fuses are redundant since there are already two fuses on the reducer already. If the reducer pictured is the one you are getting.

No, I ordered the ProChaser. But looks like that one has the input side fuse already, so I would only need the output one.

[jasonojordan]

If you are wiring it to a fused distribution block you do not need a fuse on the output side unless you are worried about a short between the reducer and the fuse block...but then that could still happen with an inline fuse so *Shrug*

Originally Posted by NinjaPixie

No, I ordered the ProChaser. But looks like that one has the input side fuse already, so I would only need the output one.

[Fairtax4me]

Are you only using the reducer to power a standard light kit? Or do you also have other accessories?
Because if it’s just feeding the light kit you can leave out the fuse box entirely.

If you need the fuse box for other things then it looks ok to me except the switch line, that should come off after the fuse, and should be for the main input power as well.
Generally the 5 wire units are key switched (meaning the switch line just comes from the key switch power). This turns off the reducer when the key switch is off.

If you wanted to kill the reducer input power entirely you need the toggle switch after your input fuse, if that’s what you were going for.


Also the fuse between the reducer and the fuse box is only necessary if you have the reducer mounted somewhere far away from the fuse box. If they’re right next to each other (like inches away) then it’s generally not needed.