fastline
Senior Member
- Location
- midwest usa
- Occupation
- Engineer
So I just learned that apparently this "50A" they refer to on RVs is 50A/240V 3 wire. I did not even realize because the "30A" they refer to has always been just a 2 wire, 120V supply. I was snowed because I don't think there are any (maybe in extremes) true 240V loads in campers.
What is the issue? Well, I have a VERY standard Onan 5500w QG series generator here and now don't know how it works. What I have realized is this 50A service is banking on the two 50A legs being opposed phases for neutral safety. The generator has a total of 4 wires off the alternator. 2 neutrals and 2 hots. It appears in the schematic that there is two discretely separate windings and such. What I suspect is the neutrals would get bonded and I would see 240V on those two hots, which would mean the two phases are 180* out.
The generator shows right in the specs as "120V" so the other thought was it really is just 120v and they have two discrete windings for a bit of redundancy? The reason I think this is likely is 5500/120 is 46A total, tapped out. Very hard to overload a neutral when the genny can't do it anyway. What is puzzling is the pigtail wires leaving the genny are only 12ga. I would expect a touch bigger I guess. I realize 12ga can do 30A and distance is very short but....
And I guess if anyone has went down this road before, I am wondering what is common for a transfer switch? I have known some guys that physically go connect their shore power cord right to the generator, which certainly serves as cross connection protection, but a transfer switch just seems more proper. ?
What is the issue? Well, I have a VERY standard Onan 5500w QG series generator here and now don't know how it works. What I have realized is this 50A service is banking on the two 50A legs being opposed phases for neutral safety. The generator has a total of 4 wires off the alternator. 2 neutrals and 2 hots. It appears in the schematic that there is two discretely separate windings and such. What I suspect is the neutrals would get bonded and I would see 240V on those two hots, which would mean the two phases are 180* out.
The generator shows right in the specs as "120V" so the other thought was it really is just 120v and they have two discrete windings for a bit of redundancy? The reason I think this is likely is 5500/120 is 46A total, tapped out. Very hard to overload a neutral when the genny can't do it anyway. What is puzzling is the pigtail wires leaving the genny are only 12ga. I would expect a touch bigger I guess. I realize 12ga can do 30A and distance is very short but....
And I guess if anyone has went down this road before, I am wondering what is common for a transfer switch? I have known some guys that physically go connect their shore power cord right to the generator, which certainly serves as cross connection protection, but a transfer switch just seems more proper. ?