1973 GMC 26' Glacier Build
- Thread starter ScottC
- Start date
If you already have a 30A shore power cord, then a PO must have already jumped it somewhere (maybe in the breaker panel) to power both sides of the panel. That's fine for one A/C unit.
The 30A power invertor is 30A DC at 12V, so it's only going to draw ~3A at 120VAC. Negligible.
Your 50A 6000W Onan already has its output jumped from one single 120V leg onto the 2nd leg at the receptacle.
Is your shore power a 30A 125V standard 30-TT plug? So you don't have two hots feeding the panel, right? There's just a ground, neutral, and one single Line 'hot', correct? It must be feeding both sides of the panel somewhere.
A single 30A shore power cord for one A/C unit is fine and the invertor isn't drawing much.
BTW, that 30-TT standard plug _I_think_ is named TT for Travel Trailer, that's my theory anyway.
The Onan Powerdrawer only puts out only 1 phase 110V power which is connected to both phases of the 50 Amp 220V generator outlet.
This does NOT provide 220V from the generator. It just feeds 110V to both sides.
Plugging into a 50 amp 220V/110V outlet at the campground provides 50 amps to each side thus makes it 100 amps at 110V available.
The coaches main breakers are only 40 amp so it is really 80 amps at 110V useable. A 2 AC coach has one AC on each leg to distribute the high loads.
I hope this helps.
This does NOT provide 220V from the generator. It just feeds 110V to both sides.
Plugging into a 50 amp 220V/110V outlet at the campground provides 50 amps to each side thus makes it 100 amps at 110V available.
The coaches main breakers are only 40 amp so it is really 80 amps at 110V useable. A 2 AC coach has one AC on each leg to distribute the high loads.
I hope this helps.
The PO did not have anything except for the Atwood 30A panel laying inside, I bought the 30A TT cord at RV auction and I also picked up a 25' 30-TT extension cord at auction.
No there is not 2 hots, just typical 3 way 30-TT wired into main 30A breaker just for temp service while I am working on it.
Scott,
I would tie the two together just to lower the line loss in the situation. Line loss is always a bigger issue (in my book) than actual ampacity.
Matt_C
Here is a diagram of the Onan 120VAC wiring. Note that in the 50A receptacle, both hot terminals are jumpered together. You could use a 50A to 30A dog-bone adapter to plug your 30A cord into the Onan receptacle. You should carry a 50A to 30A adapter in case you have only a 50A pedestal plug available to you sometime.
Notice also the Neutral and ground are connected together in the Onan since it is a primary power source.
Notice also the Neutral and ground are connected together in the Onan since it is a primary power source.
Wow 7 months later! Sorry for not updating, I got the Onan all squared away, we needed it for our trip to Michigan International Speedway for NASCAR in August, the only thing I needed to finish was the exhaust pipe so I could install an exhaust venting system. The Onan exhaust kit I purchased had a little different muffler and tailpipe so I needed to bend tailpipe, the tailpipe is 1" which is to small for exhaust bending machine so I used a method of filling the pipe with sand (pevents pipe collapsing), heating with torch and bending with longer pipe (persuader), below are pics of finished project. Link to venting system used below also, I have also seen folks make their own out of and aluminum downspout if you want to save some money.
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Here is a quick tip! I was having intermittent electrical issues with headlights, turn signals, backup lights dash lights etc. I thought I saw a video or comments about cleaning the fuse block. I pulled the fuse block and all fuses, took a look and sure enough the fuse tabs looked corroded. Took out my Dremel and with a long skinny stone cleaned up all the tabs. All issues are now gone!!!!
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I just had the same issue with my cigarette outlet circuit. I dislike glass fuses, I'll probably eliminate that whole panel soon, and swap in something with blade fuses.
Just clean them up much easier than swapping in new style fuse block, glass fuses work fine.
They won't be as good as they used to be. The plating is gone at this point. Corrosion resistance is severely compromised. Dielectric grease can help, but is messy. Then there are the rivets. Just another contact point that starts building up resistance. I've caught my fuse panel getting hot at the rivets before. It's easy to clean them up and get individual circuits working again for sure, but a replacement/upgrade is really best in the long term. I can guarantee every one of the old fuse panels has more resistance than it used to, and will have more resistance in the future.
Yours looks pretty good now after the stone work. Looks like the copper plating is showing from under the nickel plating in places though. Contact resistance at the fuse is much lower now, so that's good. But the copper will oxidize faster than the nickel did. It'll probably start getting resistive in 5 years, troublesome in 10 years perhaps. It depends a lot on humidity, and mine is VERY high for about half the year. Winter is rough on electronics at my place. Every spring there's a new list of things that quit working (too many projects also).
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I have had a long and successful experience with 3AG/AGC/SFE fuses.
Successful cleanups have been done for years with a .22/.25 wire brush from a gun shop. The pistol brush is actually better because it is shorter. I took a small piece of flat aluminum to put a tapped hole in to be a handle for the brush.
Be Aware that there are lots of CCV* fuses in the blade fuse boxes. I recently wasted an half of a beautiful day diagnosing a bad fuse in a friends car. The cheap box he bought had two defective fuses in the box. Motto: Only buy known brand fuses.
*CCV = Cheap Chinese Version
Matt_C
Successful cleanups have been done for years with a .22/.25 wire brush from a gun shop. The pistol brush is actually better because it is shorter. I took a small piece of flat aluminum to put a tapped hole in to be a handle for the brush.
Be Aware that there are lots of CCV* fuses in the blade fuse boxes. I recently wasted an half of a beautiful day diagnosing a bad fuse in a friends car. The cheap box he bought had two defective fuses in the box. Motto: Only buy known brand fuses.
*CCV = Cheap Chinese Version
Matt_C
I changed the side molding over to aluminum flat stock 1/8" x 2 1/2", Painted strips black, used butyl on seam and RTV along the top. Original stainless strips are available if anybody needs a set.
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License plate light was not working and pretty rusty so decided to change it out before I got going on the interior back panels, just made a quick piece out of plastic, painted it white, newer style housing with LED bulb.
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Unlike the way it was built, we are doing the interior from back to front, being the most used part of the coach is the bed we wanted to get that area usable first, picked up some foam for insulating and sound deadening the rear cap.
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What's the R value on that stuff? Putting anything else on top? It looks like it'll cut down a lot of noise.
Don't know the actual R value, I picked up 2 boxes at auction, 1 box plain and 1 box adhesive backed, I used the adhesive back on the ceiling and a couple wall spots, stuff worked great.
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