Grounding an Inverter?

Must be confusing equipment ground with 12 volt negative.

Flapper wrote:

Golden_HVAC wrote:
I would run a separate ground. It is only a little bit of #12 wire anyway.

Fred.

Well, if I follow directions, it's supposed to be about about 3 feet of at least #0 wire to get to the nearest frame member.....better if 1/0 or 2/0. With terminals. So it gets to be a pain in the behind to source, crimp and route....

Granted, for 120v AC, it would only be #12.....

What Band of inverter do you have? #0 cable sounds like something you would use on the 12v side for a very long run, not the 120v side.

I have two AIMS Inverters mounted in almost the same location in my trailer setup. These are about about five feet away from my main BATTERY switch on my trailer tongue area.

I run both POS and NEG INVERTER cables to this point... The 1500WATT Inverter uses a 175AMP FUSE and the 600WATT Inverter use a 80AMP FUSE (ANL/AMG Type FUSES).

I ground my INVERTER frames using separate 12-inch or so solid HD bare copper runs thru the trailer floor using proper ground lugs to the trailer frame. Each INVERTER is grounded separately (Not using the same ground lug)

Experimenting with HAM RADIOs I get stronger INVERTER RFI signals by NOT running the short solid copper ground wire to the trailer frame.

The 120VAC POWER coming from INVERTERs is very active with alot of RFI BRRRRR type signals due to their high current 12VDC switching actions to produce the AC VOLTAGEs..

A very big nemeses for HAM RADIO guys wanting to operate on 80M and 40M HF frequency ranges...

Roy ken

enblethen wrote:
The positive and the negative should be run directly to the battery.
The metallic portion of the inverter housing needs to be grounded to the vehicle frame. This is on the 120 volt side of the inverters system.

X2, the purpose is to allow for a safety ground in the event of the inverter chassis being energized. An AWG 12 wire is all that is necessary and it needs to have a path to frame ground, NOT to the (-) phase of the battery.

The positive and the negative should be run directly to the battery.
The metallic portion of the inverter housing needs to be grounded to the vehicle frame. This is on the 120 volt side of the inverters system.

I would run the two wires back to the battery (of the recommended size) and then ground the inverter chassis to your frame with something like 12 gauge. Grounding the inverter chassis to your frame keeps the Inverter box (a Faraday shield) at the same potential as the chassis which minimizes noise from the inverter. The positive and negative inputs carry a lot of current so their respective inputs at the imverter are really moving with respect to chassis ground

Flapper wrote:

Golden_HVAC wrote:
I would run a separate ground. It is only a little bit of #12 wire anyway.

Fred.

Well, if I follow directions, it's supposed to be about about 3 feet of at least #0 wire to get to the nearest frame member.....better if 1/0 or 2/0. With terminals. So it gets to be a pain in the behind to source, crimp and route....

Granted, for 120v AC, it would only be #12.....

What inverter calls for that size wire for the chassis ground? Xantrex calls for #8 on their 3kw models (minimum of 4/0 for battery cables).

I have often wondered about this myself. As near as I can tell connecting the Ground to the Negative isn't going to affect the operation of any inverter.-

Golden_HVAC wrote:
I would run a separate ground. It is only a little bit of #12 wire anyway.

Fred.

Well, if I follow directions, it's supposed to be about about 3 feet of at least #0 wire to get to the nearest frame member.....better if 1/0 or 2/0. With terminals. So it gets to be a pain in the behind to source, crimp and route....

Granted, for 120v AC, it would only be #12.....

I would run a separate ground. It is only a little bit of #12 wire anyway.

Fred.