30 amp is really 20amp

[debbiep63]

Am I the only one who pays for 30amp service only to get a 30 amp socket with 20amp or less power?? This has happened several times in the past five weeks of travel. I don't think it's nice to try and fool an RV'er.

[pianotuna]

Hi debbiep63,

Welcome to the scrum that is rvnet!

Please don't be "put off" by some of the folks here. Your possible problem sounds a bit unique.

You are still "safe" at 109 volts. (I.E. nothing will be damaged by a "brown out".)

It does sound as if there may be a problem in the RV.

Do you know where the breaker box is in the unit? If so, (and if it is in your comfort zone), disconnect from ALL power sources, open it up to where all the wires are connected, and tighten all the screws.

Do you also get this fairly large voltage drop when using a generator?

Another place where connections may be loose is in a transfer switch (if there is one).

debbiep63 wrote:
Evidently I have a problem with my coach. I was wrong about my suggestion that I was only getting 20 amps. Will have to have it serviced when I return home, if it holds out till then. Just turning on the tv drops the volts from 118 intoI the red at 109.. Will keep my questions to myself in the future and continue to just read q&a on the site. Thanks Royb for your info. It was helpful

[GrumpyandGrandm]

Could be in the CG receptacle (loose or worn) or it could be in your plug. Depending on how old your camper is the molded plug may have overheated and created a loose connection with the wire. Or as you mentioned could be another connection inside the camper. All of which could cause a voltage drop as the load increases.

[ronfisherman]

Debbie, since you are experiencing this problem at more than one campsite/park. I would suggest that you check your power cord and its connectors. Especially the end that plugs into park post. Often people find that connector/plug is getting hot when drawing power.

Please keep posting. This is a tough group. But very helpful with solving problems. Glad you posted your problem in the class C forum. The group that helps solving problems in the Tech Issues forum can be brutal. :R:B

[westernrvparkow]

j-d wrote:
First, Debbie, WELCOME!
People often "say" things with their fingertips that the rest of their senses like sight and sound wouldn't allow.
V*A=W, true enough. Problem is, appliances etc. want W, so if V goes down, A actually goes UP and A is a major cause of heat.
I just got back from a state park. Park wasn't near full, voltage started around that 118, dropped to 115, then 108, 105, caught it just under 100. Breakers tripping in the Motorhome. This is a 30A coach with 15K A/C. This was happening with only A/C and Convertor. Debbie, one of your 120VAC breakers should be Converter, but probably other things on it that you don't want to power off for long. Still, you could do a test.
So, I complain to the Park, and they send their maintenance man over. Told me he's replaced all the pedestal breakers and outlets. I said I noticed that, my problem was that my A/C was tripping the 20A breaker in the coach and sometimes both the 20A A/C breaker and the 30A main. (that can happen because one breaker heats up the other - I had a small fan blowing on the breaker panel!) Maintenance guy says they have a capital budget request, not funded, to pull all new power service in the campground, about 40 sites. But meanwhile, we were on a loop with 30A breakers and outlets. 10 sites in that loop, powered from a loop with a single One Hundred Amp Fuse! So, 30A "service" that's more like 10A, 100A source divided by possibly 10 users.
So Debbie, YES. Keep coming back.

As I have said before, I am really surprised Darwin hasn't weeded out all the incorrect electrical information posted on these forums. Surely some of these people are due to be electrocuted for messing with things they obviously have no clue about.
If you found a 100 Amp breaker serving the line, it is almost assuredly a DOUBLE POLE, 100 amp breaker, meaning there is 200 amps of service available on the line (2 x 100). Now the NEC (National Electrical Code) uses a formula to determine how many 30 amp RV pedestals can be served by a single 100 amp service. I don't have the calculation available at my fingertips, but it is more than the 200 amps that are available from the service. You find the same thing if you go to your electrical panel in your house and add up the all the breakers. Their value will far exceed the 200 amps your service is called and will likely exceed the actual 400 amps (again two lines of 200 amp service), especially if you double up the ratings of all the double pole breakers since they can deliver that stated amperage through both legs to the appliance they serve.
Voltage drop due to overloading lines can surely happen, but it is not a symptom of having 20 amp instead of 30 amp service.

[j-d]

First, Debbie, WELCOME!
People often "say" things with their fingertips that the rest of their senses like sight and sound wouldn't allow.
V*A=W, true enough. Problem is, appliances etc. want W, so if V goes down, A actually goes UP and A is a major cause of heat.
I just got back from a state park. Park wasn't near full, voltage started around that 118, dropped to 115, then 108, 105, caught it just under 100. Breakers tripping in the Motorhome. This is a 30A coach with 15K A/C. This was happening with only A/C and Convertor. Debbie, one of your 120VAC breakers should be Converter, but probably other things on it that you don't want to power off for long. Still, you could do a test.
So, I complain to the Park, and they send their maintenance man over. Told me he's replaced all the pedestal breakers and outlets. I said I noticed that, my problem was that my A/C was tripping the 20A breaker in the coach and sometimes both the 20A A/C breaker and the 30A main. (that can happen because one breaker heats up the other - I had a small fan blowing on the breaker panel!) Maintenance guy says they have a capital budget request, not funded, to pull all new power service in the campground, about 40 sites. But meanwhile, we were on a loop with 30A breakers and outlets. 10 sites in that loop, powered from a loop with a single One Hundred Amp Fuse! So, 30A "service" that's more like 10A, 100A source divided by possibly 10 users.
So Debbie, YES. Keep coming back.

[westernrvparkow]

National electrical codes allow a voltage range of 5%. That means a voltage reading between 114 volts and 126 volts is acceptable for a 120 volt outlet. Your reading of 118 is fine. Voltage and Amperage measure two separate things, and you cannot use a voltage measurement to calculate the amperage rating of a circuit.

[Gau_8]

Dont ask the question if you cant stand the answer.

[debbiep63]

,the mathematical volts times amps = wats is familiar to me. Evidently I have a problem with my coach. I was wrong about my suggestion that I was only getting 20 amps. Will have to have it serviced when I return home, if it holds out till then. Just turning on the tv drops the volts from 118 intoI the red at 109.. Will keep my questions to myself in the future and continue to just read q&a on the site. Thanks Royb for your info. It was helpful

[schlep1967]

Debbie, maybe it is the way you worded your initial post. Obviously you were not looking for an arguement, but maybe asking why you are getting the same voltage reading from your 30 amp plug you would get from your 20 amp plug. The answer is simple. Pretty much every appliance in the US uses 110-120 volt current. If you look at how the 50 amp plug is wired in the above diagram you will notice that even that only provides 120 volts from line to load. The 120 volts is there but not doing anything until you provide a path for it to "move". Now amps is a totally different measurement. The thickness or gauge of the wire determins how large of a circuit breaker and how much current (amps) can safely flow through it. Basically the current coming in to the box is limited by large circuit breakers up the line. And the current available at the box is much more than any one item in your camper can use. So as you start turning things on they They allow current to pass. 5 amps here, 10 amps there, 15 more when you run pretty much anything with a heating element. When these add up to more than the designed electrical system the breaker will kick to protect the system and prevent an unsafe condition. I know others here have more electrical knowledge than I do but that should somewhat correctly cover the basics.

[NMace]

debbiep63 wrote:
Boy howdy, I really opened a can of worms With all appliances off or unplugged my volt meter is readin 118.The only item I can't turn off (because I don't know how) is my converter. Suffice it to say I am cured of asking any further questions, but will continue to read all q&a for all sights..

Please don't be scared off, while some of the questions were curt, they were only seeking information to help you.

Some of these guys annoy me, too, but most know their stuff.

Ask away.

[n7bsn]

debbiep63 wrote:
Boy howdy, I really opened a can of worms With all appliances off or unplugged my volt meter is readin 118.The only item I can't turn off (because I don't know how) is my converter. Suffice it to say I am cured of asking any further questions, but will continue to read all q&a for all sights..

Sorry, but the above answer reinforces the assumption that you don't understand the question you are asking.

There is nothing wrong with the line voltage reading 118V, it might be lower then 120v, but for the reading off some uncalibrated meter, at the end of a run, it's not bad.

If the line sags more then that, say with the A/C running, then maybe you have a line-sag issue.

NOTE: This is NOT the same thing as saying you don't have a 30 amp service. Line-sag can be caused by a number of issues, including the entire park being poorly wired.

[debbiep63]

Boy howdy, I really opened a can of worms With all appliances off or unplugged my volt meter is readin 118.The only item I can't turn off (because I don't know how) is my converter. Suffice it to say I am cured of asking any further questions, but will continue to read all q&a for all sights..

[naturist]

I, too, wonder what lead you to conclude you only got 20 power. Was the plug connected to a 20 amp breaker?

[RoyB]

This is a typical camp ground diagram of the 50AMP and 30AMP service...

The only difference between the 30A service and a 20AMP service would be the type of receptacle used and the rating of the circuit breaker.

If you have a standard RV30 amp connector along with a 30AMP Circuit breaker then you should have 30AMP service.



Roy Ken

[time2roll]

So there is a 20 amp breaker supplying the 30 amp connector?
Never seen it. To my limited knowledge this does not meet NEC standards.