where do i ground for a 3 wire volt' reducer

[EZHO]

Have a 3 wire 36v voltage reducer , tests great with 12.5v out with yellow wire . but theres no ground, out wire .
so yellow goes to pos'/hot buss bar , But where do i ground my neg'/ground buss bar to ?
.
No name on my reducer and the one online had no mfg' name / http://www.performancepluscarts.com/voltage-reducers-4/
.
I'm thinking end of pack negative , but isnt that part of the 36v system somehow
found only one diagram on line and mounting the box/unit is the ground /but we never ground to frame ?
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already blew a headlight by guessing on some other wiring so / ask first, ground later is my new motto

[Mooncarter]

Yellow out 12v. Ground accessories to -bar, and run bar- to pack neg. Do not ground to frame.

[EZHO]

does it have to be end of pack neg ? or any neg'
my bus bars are on oppisite side of cart to end of pack neg' , so if it doesnt matter it would save me running 4 feet of wire
.
and you say do not ground to frame do you mean the box/unit itself ?
diagram on line and mounting the box/unit is the ground , so will that create a frame ground for the system

[BobBoyce]

Originally Posted by EZHO

does it have to be end of pack neg ? or any neg'
my bus bars are on oppisite side of cart to end of pack neg' , so if it doesnt matter it would save me running 4 feet of wire
.
and you say do not ground to frame do you mean the box/unit itself ?
diagram on line and mounting the box/unit is the ground , so will that create a frame ground for the system

Never ground anything to the chassis frame. Always ground your electrical accessories to the pack negative. The black wire on the reducer should be a common negative point that connects to pack negative, and your 12V negative bar.

Bob

[EZHO]

Originally Posted by Mooncarter

. Do not ground to frame.

.[QUOTE=BobBoyce;1449121]Never ground anything to the chassis frame.
.
.
Ok ..thanks guys
/
I just still have trouble understanding why when i use the frame for a ground with my multi-meter black lead, and put the red/ pos lead of my multi-meter on the end of line neg' batt' pack . why does it show -38.5 v / when I'm using the frame for a ground with the multi-meter ,when if the whole system is supposed to be a complete independent loop from the frame (just the way a battery works i guess ? )
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and i dont really need to know so ...

[Mooncarter]

Do your instructions say mounting the unit creates a ground to the frame?

[EZHO]

No instructions , no name on my reducer and the one online had no mfg' name / http://www.performancepluscarts.com/voltage-reducers-4/
.
but looking at goggle images there was my reducer type / 3 wires . and it clearly showed a screw going thru the mounting hole with the ground symbol
it was a mfg print not homemade .tried to find it again , no luck
. but hooked it up and tested it both ways. with it in hand and bolted to frame , all good ,no difference . 12.5 v
and the frame ground thing with multi meter no change in hand or mounted
so thats not whats causing the -36.8 v reading if thats why your asking

. so all good thanks again