clarification of gen 3 wall connector torque specs

[chalooch101]

I am installing a gen 3 wall connector on a 60 amp breaker - using #6 gauge thhn for the current carrying conductors and #10 gauge thhn for the ground conductor. The torque specs in the manual state using 50 inch lbs for the 3 terminals. Is 50 inch lbs of torque too much torque for the smaller #10 gauge wire and can possibly cause damage when tightened? Should I use #8 gauge thhn instead?

 

[Sophias_dad]

You should use what the manual specifies. If it had to be different for different gauges they'd call it out in the manual. Note that that's 50 inch lbs, not 50 ft lbs. You'll blow right through the baseplate if you try 50 ft lbs. You really need an appropriate torque screwdriver or 1/4" drive torque wrench, because the usual car handyman 3/8" torque wrench won't correctly register the 4 ft lbs you need.

N.B. Consider using ferrules for the #6. It makes a better connection because they keep the wires from splaying. Not super important.

And no, definitely don't use #8. #8 THHN is only good for 50 amps and because it MUST be derated for EV charging, you could only use 40 amps.

 

[Sophias_dad]

You should use what the manual specifies. If it had to be different for different gauges they'd call it out in the manual. Note that that's 50 inch lbs, not 50 ft lbs. You'll blow right through the baseplate if you try 50 ft lbs. You really need an appropriate torque screwdriver or 1/4" drive torque wrench, because the usual car handyman 3/8" torque wrench won't correctly register the 4 ft lbs you need.

N.B. Consider using ferrules for the #6. It makes a better connection because they keep the wires from splaying. Not super important.

And no, definitely don't use #8. #8 THHN is only good for 50 amps and because it MUST be derated for EV charging, you could only use 40 amps.

I realize I misread your #8 question. I see now that it was intended specifically about the GROUND wire. There's not much downside(aside from the difficulty in passing it through the conduit(you ARE using conduit for these wires, yes?) and the added expense. There's also no real upside. BTW, I don't think you need to use THHN for the ground wire at all. Plain bare non-stranded #10 would be fine.