30 amp is really 20amp

You might want to check/tighten the lug screws on your breakers. And 30A plugs are notorious for being worn out and over heated. Feel yours next time when the AC, etc is on and if it feels warm, replace it. ALso look at it to see if it is discolored or the rubber looks melted.

j-d wrote:
The way the park maintenance man described it to me, the "loop" of 10 sites was served by one loop of cable, wired to 30A pedestal outlets, and served by one 100-amp fuse. I asked, Fuse, not Breaker? Yep, Fuse. The kind that looks like a big firecracker with a thick copper blade sticking out of each end? Yep. Park was probably built by the CCC in the 1930's. Doubt it had electricity at all at first, but sounded like the power could have been 1960's vintage...

Yes, probably really old wiring with worn and loose connections, those are the kind of things that cause a lot of voltage drop, and my guess is the service at the main isn't the best of the best. However, unless that 100 amp fuse is blowing all the time, or has been replaced by a copper penny (like we did in the good ole days), the circuit isn't being overloaded with those ten 30 amp connections. If it was the main would trip, or in this case, the main fuse would blow.

The way the park maintenance man described it to me, the "loop" of 10 sites was served by one loop of cable, wired to 30A pedestal outlets, and served by one 100-amp fuse. I asked, Fuse, not Breaker? Yep, Fuse. The kind that looks like a big firecracker with a thick copper blade sticking out of each end? Yep. Park was probably built by the CCC in the 1930's. Doubt it had electricity at all at first, but sounded like the power could have been 1960's vintage...

debbiep63 wrote:
Just turning on the tv drops the volts from 118 intoI the red at 109

Ah ha! We can help with that ;)

With the tv on I would start by taking measurements at the pedestal and compare with the tv outlet to discover if the issue in the RV or at the pedestal.

Low voltage can be hard on some things so lets get this fixed.

If you are back home... give it a test there. If good at home then your first post was probably correct in that the campground supply was marginal. Reasonably common in older parks.

Many connect their RV with a power protection device that will cut power if voltage is out of spec, reverse polarity, bad ground and protects against minor power surges.

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

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.

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

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.

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.

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.