Community Forums

TQ60 · 06-14-2011, 03:35 PM

I will assume the OP wants to get an extended reach past the normal length of the standard cord.

There is more to a cord than just 50 or 30 amp.

The wire size is based on BOTH the current and the length.

So a #10 wire will carry the 30 amps of current, this is the MINIMUM size, but as we add length to the cord the resistance in the wire will require a heaver cord to compensate for "cable losses".

So a 50 amp cord will have the heavier weight due to the larger wire size and extra conductor, but due to the larger wire size it is more suitable to fit the need.

So the short answer is if you plan on picking up an off-the-shelf cord and do not want to do any calculations involving cable losses you are best to buy a 50 amp cord.

Now if one wants to have the longer cord, and reduce the weight while addressing the cable losses, they could determine the minimum wire size required to transport the 30 amps across the distance required, and purchase a 3 conductor cable and create their own custom cord.

But this is only valid if the original cord length is also propery sized to insure minimal cable losses.

JMonroe · 06-14-2011, 03:54 PM

If I was only going to buy/carry one, I'd buy the 50 amp, and a 50 to 30 amp adapter. Yes, it's more expensive and heavier but again, you won't use it often. I have, however, been in campgrounds (usually government of one level or another) that will have 50 amp available, but will skimp and only put in one post for every two sites. If you're on the wrong side, that extra length will be useful.

bluepill · 06-14-2011, 05:23 PM

In my MH I can run both A/C units and the fridge pulling 26 amps, so 30 amps is enough for limited use. If I need to run the microwave or 120 volt water heater, I just turn off the A/C while doing so. For the few times that 50 amps is not available it's no biggie for me.

Alan_Hepburn · 06-14-2011, 05:43 PM

Another thing to think about - if you are connecting the 50A RV to a 50A supply through a 30A cord you're asking for trouble. If you're never going to try and connect to a 50A pedestal then a 30A cord will work but if it were me I'd go for the 50A cord to be safe.

wildtoad · 06-14-2011, 06:02 PM

Quote:

Originally Posted by Alan_Hepburn

Another thing to think about - if you are connecting the 50A RV to a 50A supply through a 30A cord you're asking for trouble. If you're never going to try and connect to a 50A pedestal then a 30A cord will work but if it were me I'd go for the 50A cord to be safe.

Agree. The "system" does not know that you are trying to pull 50 amps thru a 30 amp pipe and thus could melt the 30 amp wire.

RJay · 06-14-2011, 06:10 PM

You cannot connect 50 amps thru a 30 amp cord since there is only one live leg in a 30 amp cable and you need 2 live legs for a 50 amp cable. Your EMS will sense only once live leg therefore limiting the load to 30 amps.

bldrbob · 06-14-2011, 07:58 PM

I know I will hear that it is wrong but I made an extension using 10/4 .I never use the full 50 amps and it splits the load between two hot leads.The #10 is much easier to handle and the four wires will handle the loads I have.It is better than a 30 amp cord that would only have 3 wires.

IRVTrekin2 · 06-14-2011, 10:18 PM

I bought the 50A cord way back in 2000 when I had my 5th wheel. If I had it to do over I would buy the 30A cord. I have only had to use it very few times in the 11 years and every single time I needed it because of poor campground layout of the electrical box, they only offered 30A service. I have never had a campground that offered 50A service where my main cord wouldn't reach.

hooverbill · 06-15-2011, 12:05 PM

50A...that 30A is no good if you need all that power that a 50A provides and only have a 30A cord. If you shop around you can find one that is not as expensive as others.

JimM68 · 06-15-2011, 12:11 PM

I bought a 30 amp extension when I had my ole pace arrow, and it came in handy a few times when I wanted to park backwards to be awning to awning with friends.

I also use it to plug in at home.

With the new coach, I've yet to need it anywhere but at home, and have not missed it not being 50 amp.

That said, if I didn't have it and was buying one for the new coach, i'd buy a fifty.

IRVTrekin2 · 06-15-2011, 03:05 PM

Quote:

Originally Posted by hooverbill

50A...that 30A is no good if you need all that power that a 50A provides and only have a 30A cord.

My point was that it doesn't matter if you have a 50A cord if the pedestal only has 30A of service that is all you are going to get, and in my situations that was all that was available. Like I said before every time I needed an extension there was only 30A of service at the pedestal, I have never needed an extension where there was 50A of service available.

JSW · 06-15-2011, 03:21 PM

I have both and have used both. We don't always park at a camp ground, sometimes we stay with friends and have to run the cord 50' or so. I have found it is much better, especially in this hot, Texas weather, to use the 50 amp cord. I just about melted the plug on my 30' last week while connected to a 30 amp outlet. Be careful, that wire does get hot!

dvmweb · 06-15-2011, 08:58 PM

Get the most power you can....period. If you are plugging in then get as close as you can with 50 amp (it's called that for a reason, 220 v, 50 amp) then adapt. Remember you are going back to 120 volt. The difference is significant. Have you ever used a 220v vs 120 v welder? Then, you can understand the difference. Sort of like using a bigger hose, big wire, lower resistance. I only use one AC on the adapter. Don't want to brown out the motors. Need lots of juice to get going.

Wayne M · 06-16-2011, 06:02 AM

I was very fortunate. Somewhere along the line I picked up some electrical cord, #6-4. I bought the male and female end plugs and built one myself. Real cheap. So check out your local electrical supply, or Lowes and see what the cost is for a run of 30 feet or so. You may be surprised that it is a lot cheaper than the RV stores, and the cable is a lot more flexible. I carry mine all the time. It is rolled up in the bottom of the electrical cable compartment with the OEM hard wire rolled up on top of it. I do not find it difficult to handle.

I recently was at a CG that was a pull-in. My OEM was about 6ft short of where they had the electrical outlet. I was glad I had the 50 amp, as it got real hot a couple of days and the two stage AC did not miss a beat. If at all possible, go with the 50 amp. As Rusty stated you will have the best of both worlds.