Understanding U300 Shore Power Connections

Topic: Understanding U300 Shore Power Connections (Read 775 times) previous topic - next topic

Understanding U300 Shore Power Connections

August 01, 2018, 04:09:35 pm

The attached photos illustrate the components I found for my shore power system. I would appreciate comments regarding the following questions:

1. Is the receptacle in the white cabinet next to the outside water faucet the receiver for tge 50 amp service? (I have a long, very thick cord (shown below) that I believe fits this receptacle, with the other end wired for the pedestal.)

2. Below this white console is a smaller, hard-wired cord (shown with plug hanging out of bay). Is this the 30a shore service cord?

3. In the photo next to the heavy (50a) cord is a very short cord, looks to be possibly a 15a adapter?

And finally...

4. Do members here recommend a surge protector in between the shore power plug and the pedestal?

Thanks to all who reply!

Re: Understanding U300 Shore Power Connections

Reply #1 – August 01, 2018, 04:21:45 pm

Welcome

That round connector is a twist connector for your 30a cord. (Oops) that is a 30a Looks like you also have a direct 30A cord.. you have a 50A to 30A doggone the short cord.

Do you have a larger round plug with 4 male twist locks.. that is the 50a

Looks like PO previous owner did some re-wire, be careful

Can you take a photo of this entire bay?

Yes I always use a pedistal surge protector. Some coaches they are built in..

Feel fee to ask more questions. Beamalarm.com is our go to information reference site, many contributors.
Started by Berry Beam!

Re: Understanding U300 Shore Power Connections

Reply #2 – August 01, 2018, 04:30:37 pm

Thanks John.

Will take more photos. Do not know of any re-wiring; none reported.

Re: Understanding U300 Shore Power Connections

Reply #3 – August 01, 2018, 04:46:55 pm

After almost burning down our coach, we bought this EMS. We summer in 'monsoon country' and always unplug from the pedestal should lightning be in the neighborhood!

Rv Surge Protection | United States | Progressive Industries, Inc.

Re: Understanding U300 Shore Power Connections

Reply #4 – August 01, 2018, 04:57:46 pm

As far as I can tell from the photos you have a 50 amp setup. 50 amps has one ground one neutral and two 120 volt terminals. On yours the ground will be at the side of the plug that goes into the TV. It's an older style. The end that goes into the pedestal will have four prongs. If you are competent to do this measure with a meter the voltage at the coach end of the cord between the ground and each terminal you should have 120 volts on two terminals and zero volts on the other. The blades/sockets that have a bent piece on the side carry the current. The straight one is the neutral and the ground is at the side of the plug.

Surge protector? Absolutely

If you are not sure have an RV tech check it out. NOT AT CAMPING WORLD!!!.

Found the pic below that may help. "C" is the neutral.

Keith

Re: Understanding U300 Shore Power Connections

Reply #5 – August 01, 2018, 05:58:26 pm

I bought the Surge-Guard...

Re: Understanding U300 Shore Power Connections

Reply #6 – August 01, 2018, 06:08:57 pm

Keith,

Thanks very much. This should give me the data and visuals I need to fully understand my plugs and cords.

I'm still perplex though, about why there is the plug inside tge white box, plus the hard-wired cord three-pronged male plug. Why two different power cords?

Re: Understanding U300 Shore Power Connections

Reply #7 – August 01, 2018, 07:36:07 pm

I would trace out that 30 amp male cord to see where it goes and if it is hot when you are plugged into 50 amp service

Re: Understanding U300 Shore Power Connections

Reply #8 – August 01, 2018, 08:09:02 pm

Quote from: red tractor – August 01, 2018, 07:36:07 pm

I would trace out that 30 amp male cord to see where it goes and if it is hot when you are plugged into 50 amp service

Second that!! If the 50 amp receptacle has not been disconnected.................. seems pretty certain that the 30 amp male plug on the cord would be hot when plugged in shore power.

definitely need to know where the other end of the power cord is connected.

Re: Understanding U300 Shore Power Connections

Reply #9 – August 01, 2018, 08:25:35 pm

Yes to the above concern about the 30 amp plug. It may be that the previous owner wired it for both services and there is a change over switch somewhere. Before code required GFI protected outlets at the pedestal you could purchase a cheater box to plug into both 30 amp and 20 amp outlets to give you more power. They don't work now. Maybe it's someones half-a$$ed try at something similar. I would get it checked out by someone who knows what they are doing. Make sure that they understand RV wiring as it's different to 50 amp house systems that can give you 240 volts!

Keith

Re: Understanding U300 Shore Power Connections

Reply #10 – August 01, 2018, 08:59:14 pm

Thanks to all... The coach is headed back to the shop to get this sorted out.

Re: Understanding U300 Shore Power Connections

Reply #11 – August 06, 2018, 06:23:45 pm

We got it sorted out. Took a few minutes, had to take some panels apart:
30 AMP cord goes to a small transfer switch, which is hooked to the rear air only.
50 AMP, still functions like normal. No power cord ends are hot when plugged in.Rear air works normal on gen set and shore.
I am going to guess, when only 30 amp was available, the previous owner wanted to be able to run the rear air.
He could plug the 30 amp cord into a 20 amp plug (with adapter) and plug the 50 amp into 30 with an adapter.
Actually kinda cool (pun intended)
Chris

Re: Understanding U300 Shore Power Connections

Reply #12 – August 07, 2018, 02:03:19 am

Years ago had a Bounder wired the same way. The rv originally came with a switch for front or rear A/C selection. Previous owner wired rear air to separate 30 amp service plug also similar to yours. Knowing this did not allow gen to run rear a/c, he said he only camped where plugged in. That did not fit my use, and so I rewired to original stock configuration.

Foretravel Owners' Forum For owners and Fans of Foretravel Motorcoaches September 13, 2025 ...

Understanding U300 Shore Power Connections

August 01, 2018, 04:09:35 pm

Re: Understanding U300 Shore Power Connections

Reply #1 – August 01, 2018, 04:21:45 pm

Re: Understanding U300 Shore Power Connections

Reply #2 – August 01, 2018, 04:30:37 pm

Re: Understanding U300 Shore Power Connections

Reply #3 – August 01, 2018, 04:46:55 pm

Re: Understanding U300 Shore Power Connections

Reply #4 – August 01, 2018, 04:57:46 pm

Re: Understanding U300 Shore Power Connections

Reply #5 – August 01, 2018, 05:58:26 pm

Re: Understanding U300 Shore Power Connections

Reply #6 – August 01, 2018, 06:08:57 pm

Re: Understanding U300 Shore Power Connections

Reply #7 – August 01, 2018, 07:36:07 pm

Re: Understanding U300 Shore Power Connections

Reply #8 – August 01, 2018, 08:09:02 pm

Re: Understanding U300 Shore Power Connections

Reply #9 – August 01, 2018, 08:25:35 pm

Re: Understanding U300 Shore Power Connections

Reply #10 – August 01, 2018, 08:59:14 pm

Re: Understanding U300 Shore Power Connections

Reply #11 – August 06, 2018, 06:23:45 pm

Re: Understanding U300 Shore Power Connections

Reply #12 – August 07, 2018, 02:03:19 am

Affiliate Notice