48V to 12V Reducer and Accessory Wiring Instructions

[VigorDefiance]

I have a 2016 Precedent, 6x8V batteries = 48V

I recently purchased the following and need help hooking up:
4-wire 48V to 12V reducer: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Fuse box: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Accessories: RHOX LED Light Kit http://www.golfcart.com/images/LGT-306L.pdf
USB 12V: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
12V 20A switch:
https://www.amazon.com/gp/product/B0...EFRDRGT4&psc=1

I laid out the connections below and there are a few questions at the bottom. Thanks much for all of your help!

1. Connect 48V+ from reducer to + on first battery post
2. Install in-line 20A fuse in between + battery post to 48v+ reducer
3. Connect 48V- from reducer to - on last battery post (other side to get 48V total)

4. Connect 12V+ from reducer to fuse box
5. Install in-line 20A fuse in between 12V+ from reducer to fuse box
6. Install 12V 20A switch in between 12V+ from reducer to fuse box, run switch to dash
7. Connect 12V- from reducer to fuse box

8. Wire each accessory from fuse box
a. Rhox LED lights (LGT-306LB) with bucket harness
b. USB charger

Q1: What gauge wire should I use on the 48v side?
Q2: What gauge wire should I use on the 12v side?
Q3: How do I find the positive and negative connections on the Rhox LED light kit to wire to the fuse box?
Q4: Anything I am missing or is wrong above?

[R&TBabich]

Originally Posted by VigorDefiance

.... Q1: What gauge wire should I use on the 48v side?
Q2: What gauge wire should I use on the 12v side?
Q3: How do I find the positive and negative connections on the Rhox LED light kit to wire to the fuse box?
Q4: Anything I am missing or is wrong above?

I'm just starting a similar upgrade.
I'll probably use 14 ga wire, but 16 ga should work fine.
The 12v side will use a larger gauge.
I like to run larger gauge wire so the fuse blows and doesn't melt the wires.
I would add a 48v relay triggered by the ignition switch in the power line to the reducer.
That way everything is shut down when the ignition is off.

[VigorDefiance]

So would 14ga be good for 48v and 12v sides?

Any thoughts on what relay to get?
Any help on diagrams to wire that in?
I have a 2-pin ignition if that helps.

Thanks much for the help!

[Andy4639]

All grounds have to go back to the reducer 12 v ground. No grounds to the fuse block. No need in a fuse between the reducer and fuse block. Does your reducer not have the key switch ON/OFF wire to hook to the key switch?

Here is the schematic for the one I just installed in little RED. It cut's ON/OFF with the key.

[yawood]

Originally Posted by VigorDefiance

I have a 2016 Precedent, 6x8V batteries = 48V

I recently purchased the following and need help hooking up:
4-wire 48V to 12V reducer: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Fuse box: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
Accessories: RHOX LED Light Kit http://www.golfcart.com/images/LGT-306L.pdf
USB 12V: https://www.amazon.com/gp/product/B0...?ie=UTF8&psc=1
12V 20A switch:
https://www.amazon.com/gp/product/B0...EFRDRGT4&psc=1

I laid out the connections below and there are a few questions at the bottom. Thanks much for all of your help!

1. Connect 48V+ from reducer to + on first battery post Yes
2. Install in-line 20A fuse in between + battery post to 48v+ reducer Yes, close to the battery
3. Connect 48V- from reducer to - on last battery post (other side to get 48V total) Better to connect it to B- on the controller. Does your model have a black wire with a yellow bullet connector behind the batteries? If it does, connect to that.

4. Connect 12V+ from reducer to fuse box Yes
5. Install in-line 20A fuse in between 12V+ from reducer to fuse box Not necessary
6. Install 12V 20A switch in between 12V+ from reducer to fuse box, run switch to dash You can do it that way but your reducer will run constantly. Better to put a relay in to switch the reducer on and off - this can be done from the key without a separate switch
7. Connect 12V- from reducer to fuse box To the negative buss part of the fuse box

8. Wire each accessory from fuse box Yes, just be sure that each accessory -ve goes back to the negative buss connection in the fuse box
a. Rhox LED lights (LGT-306LB) with bucket harness
b. USB charger

Q1: What gauge wire should I use on the 48v side? You have bought a 10A reducer so the output is 12V x 10A = 120W. On the 48V side you have 120W = 48V x ?amps so your amps are 120/48=2.5 amps. The attached chart shows that you only need 16 gauge.
Q2: What gauge wire should I use on the 12v side? As the 12V will be carrying 10A, 14 Gauge would be best although it could get away with 16 gauge.
Q3: How do I find the positive and negative connections on the Rhox LED light kit to wire to the fuse box? They are probably marked but just get a 12V source (e.g. car battery) and try them one way or the other. If you have them wrong the first time it won't hurt the LEDs they just won't light.
Q4: Anything I am missing or is wrong above?
See my diagram as to how to hook this up with a relay so that you turn the reducer itself on or off with the key. If the reducer is off, all your accessories will be off.

My answers are in red

[mfinnegan]

you can absolutely put accessory grounds on the fuse box ground.