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Hardwiring Inverter AC Line

chrisski

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How do you hook the AC ground in the three pair cable for the AC out hardwire cord to your inverter? My AC ground has a #6 stud, but I don't see how to get an 8 AWG wire to fit that stud. I'm sure I'm missing something obvious.

First time hardwiring an Inverter. I have a 3000 watt 24 volt inverter (SAMLEX PST 3000-24). So of course, I want to follow the instructions. It calls for 14/3 Loomex - 8/3 Loomex. I open it up and the inverter has a receptacle with a screw set 8 AWG will fit in the Line and Neutral line that I will crimp a wire end terminal over, but the AC ground is a #6 screw.

I can't seem to find an 8 AWG to #6 ring terminal or an 8 AWG to 3.5mm ring terminal. Amazon, Google, or Ebay: none have this.

Below are a couple of excerpts from the Samlex manual. THis shows the cable size and the AC ground stud size.

1642123711657.png
This shows where the hardwire will be inserted. 13 is the line and nuetral where I hook 14 AWG - 8 AWG wire. 12 is a #6/3.5 mm stud where I hook the AC ground to.
1642123805452.png
 
My question is not really about the 8 AWG wire size I am using nor whether 14, 12, 10, or 8 is better. More about do most inverter use a comparatively small stud to attach the AC ground.

The inverter allows up to 8 AWG wiring in the line and neutral to be easily attached, but I am surprised that the AC ground is attached with a #6 stud. That seems really small.

After two days of searching, I just found a couple of 8 AWG to #6 studs, whereas before today, my searches were empty. I would think that if an inverter allows 8/3 meaning a 8 AWG to #6 stud, that this connector would be readily available. Searched several local stores and tried several different terms on google, amazon and E-Bay, and after tso days, found three differenet Molex Crimp Terminals:

DIGIKEY 8 AWG to #6 Ring Terminals
 
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I installed a new electric range last year fed with 40 amps 240v #6 aluminum with a seemingly tiny #6 or #8 stud on the appliance. The connectors at Home Depot were all made for something larger but it all works fine. I don't think you will have any issues.
 
The safety Ground wire for AC circuit has to be at least the same gauge or larger to handle fault current as the L and N wires so when fault current occur it will able to trip the circuit breaker without the burning up the wire, seems to be bad choice that they install #6 stud instead of #8 or #10 stud place.
 
I installed a new electric range last year fed with 40 amps 240v #6 aluminum with a seemingly tiny #6 or #8 stud on the appliance. The connectors at Home Depot were all made for something larger but it all works fine. I don't think you will have any issues.
I have always read the ground can be a size smaller on larger wire bundles. Dead short of 50 amps through #10 will trip the breaker instantly with no harm to the wire.
 
The safety Ground wire for AC circuit has to be at least the same gauge or larger to handle fault current as the L and N wires so when fault current occur it will able to trip the circuit breaker without the burning up the wire, seems to be bad choice that they install #6 stud instead of #8 or #10 stud place.
I think that is odd, but this is a SAMLEX inverter which is supposed to be a pretty decent inverter.

I’m also supposed to crimp the ends of the line and neutral with cord end terminals. I guess these crimp into a square, I’d always thought they’d stayed round. Never heard of that name, but I’d seen ferrules and assumed they crimped round, but actually is square. This is what I’m going to add to the line and neutral ends:

80F47D6B-7399-4851-B196-B2F79B9F439D.jpeg
 
I have always read the ground can be a size smaller on larger wire bundles. Dead short of 50 amps through #10 will trip the breaker instantly with no harm to the wire.
I was wondering if the instructions should have said two pair wire 14 AWG to 8 AWG with a smaller AC grounding wire. There’s probably a more proper name to that wire. I do see this two pair wire with a smaller grounding wire for sale.
 
the ground isn't really meant to carry current for any length of time, it's fine to use a smaller conductor for the job. for instance, I run 240v AC about 100' to my house from my inverter, for that I use 4/0 wire as the conductors. the ground, however, is only 6awg. it just needs to be large enough to handle a short surge that allows breakers to trip.
 
I run an EVO-4024.
The wire Ferrules are for stranded wire, not solid core 14/3-8/3 as it is not needed.
I run 8/3 from Inverter to AC Panel. (Stranded, requires ferrule.)
L5:30 input comes in via 10/3 to 40A Breaker then to Inverter.

Inverter Chassis Ground uses 8AWG to common ground. (I am landbased, not mobile )
Inverter Ground is bonded to the Ground
REMEMBER THE NEUTRAL to GROUND BOND... See docs !

WARNING: The torque on the molex connector screws must be correct and should be recheched after put into use. If using Ferrules you can actually drive the screw down into the ferrule, IF that happens, forget getting the screw out, you have to pull the molex bar (real PITA).
 
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