My son just purchased a home with a detached garage and I was initially excited to find they had connected the buildings with 1-1/2" buried Sched 80 PVC and a 50amp circuit as the previous owner was a welder. I have an electric car and was thinking this would be perfect for my Level 2 charger. On further inspection the line is a SE 6-6-6 AL starting at a 50amp breaker in the main load center and terminating in an old 6-50R attached to the garage wall. The run is roughly 100 feet, partly attached to support beams in the basement and the rest through the PVC.
I have a couple of issues:
- At this distance my calculator indicates this should only be rated at 40amps with the 6 AL cable.
- I had thought I would put a sub panel in the garage but I don't see anyway to do that with the 6-6-6 as I need the 4th conductor, necessitating replacing the whole thing.
- They used metal staples to secure the cable which makes me worried about damage (see pictures)
In the short run I thought I would downgrade the breaker to 40amps; my car can draw 30amps max with charging, I don't need 50amps right now. But I'm wondering how concerned I should be with the potential for staple damage to the sheathing.
Also, is there any legal way to get a 4th conductor without replacing the whole thing?