Our shakedown cruises are ongoing although the big cruise has been cancelled. We were supposed to take the new Barth on a trip to Disney World in October but due to time constraints and cost differential, we will be flying. That will make a trip to Washington DC in July 2008 the first big one.

So, as we get ready to embark on another short trip to Estes Park Colorado, I find many of their RV Parks only have 30 amp service and their fees are ala carte i.e. additional charges for each child, dog, extra vehicle, 50 amp service if available, premium service - whatever that means, cable TV, etc. I've been avoiding some of the RV parks that don't have 50 amp service.

I've been told I need 50 amp for this coach. Although I know I don't have to have 50 amp, what am I losing by having only 30 amp or less? Does that mean I won't be able to run both A/C's or watch a movie? I think I need one of those RVing for Dummies books.

The only likely handicap is inability to run both a/c's simultaneously. 30A service was standard until big coaches with high electrical demand became common. It should handle at least one a/c, plus the demand of a converter, a microwave & a tv. You'll know you're trying to do too much if you pop a breaker.

Outstanding! That isn't enough reason to avoid the 30 amp parks, thanks!

The guys here that know electricity much better than me convinced me that you should invest in a decent voltmeter and check the power box before plugging in the coach. They can vary wildly, I understand.

"...decent voltmeter and check the power box before plugging in the coach. They can vary wildly, I understand."

N.B. Electric utilities maintain voltage is acceptable if it is 10% above or below the stated voltage, i.e. 110 volts. This means anything from 99 volts to 121 volts is "official" and okay to use. "Low voltage" is a bugaboo seldom encountered. If the voltage is too low the wires will heat up and trip the supplying breaker. Often parks supply 125-130 volts and nobody gives that a thought. I, for one, never worry about that.

And since you mentioned it, I would HIGHLY recommend "The RV Handbook" by Bill Estes. Here's the Amazon.com link to the product, and I believe I bought mine from the "Used" products section for a fraction of the new cost.

99 volts is pretty low for an air conditioner.

I wonder if that ten percent rule should be applied to 120 volts instead of 110.

quote:

Originally posted by bill h:
99 volts is pretty low for an air conditioner.

I wonder if that ten percent rule should be applied to 120 volts instead of 110.

I thought the same thing too.

Lower voltage in = higher amp draw.

99v seems way too low for my taste. I would think at that voltage for a "static reading" it would dip below anything the amp load could handle and force a circuit trip or burnout.

quote:

99 volts is pretty low for an air conditioner

Lower voltage in = higher amp draw.

Yeah. If the voltage is too low, the breaker trips (preventing damage, which is what it is designed to do).
Recently, one of my fellow travelers had to disconnect his expensive "voltage monitor" device which "protects his RV" because the RV Park voltage was running right at 129 and his "protector" kept shutting off his shore power.
I'm not debating, only reporting what I know to be true, at least in my parts of the world. Nowadays, most "110" is above 120 and often 125-130. Should we be nervous about "high voltage"? Apparently not.

If you are not comfortable with testing the pedestal with a meter, you might look into the new circuit analyzers Camping World is starting to carry. Go to campingworld.com and search for 'circuit analyzer'. There is a 30-amp and a 50-amp version. Both are reasonably priced and also provide surge protection.

Mike

If you are not comfortable with testing the pedestal with a meter, you could use a test light. If you use a 120 volt bulb, each hot to ground will light up the bulb. Each hot to neutral will light the bulb. Hot to neutral will not light, and hot to hot will do a CAMELOT. That is, a "Brief and Shining Moment".

Now, if you want to use your test lamp more than once, use a 240 volt lamp. It will be dim on each hot to ground, dim on each hot to neutral, out on ground to neutral, and bright on hot to hot.

A plug in tester can also be made using brass strips epoxied to a plywood or phenolic base with a 220 volt bulb reading hot to hot, and 110 volt bulbs reading the rest. Dye the bulbs for hot to hot, both hots to ground, and both hots to neutral green. Dye the neutral to ground red. All greens should illuminate and the red should not. If you can't find a 240 volt bulb, use a 120 volt one with a dropping resistor.

This hot to hot reading is important. Some shady campground operators have wired their 50 amp receptacles so that the hot to hot reading is 0 volts. Things will work, but you could fry a neutral wire at an inconvenient location or start a fire. The two hot poles need to be 180 degrees out of phase with each other to avoid the possibility of an overloaded neutral wire. When corrected properly, the neutral wire carries the difference between the currents in each hot wire. When the hots are connected incorrectly, the neutral wire carries the SUM of the currents, which could be an overload. And since neutral wires are not protected by a breaker, the overload continues until meltdown.

Having said all that, the overload mentioned is most likely to occur when the rear air conditioner is operated. So, one could take a chance and connect to an improperly wired 50 amp outlet and not draw too much current from the second hot leg. My own preference would be to operate only one hot leg by shutting the other one off with the breaker on the post. Try each breaker and you will know which one powers the circuits you want. However, those type hookups often have 30 amp wiring, so don't operate too many appliances at once.

We have a little meter that plugs in an outlet and lets you know the supply. If the meter is in the green we use what we want, if the meter is in the red we use everything sparingly.

The meter is sold at Camping World for about $30, I think, but I could be way off. I am sure the meter is not exact, but gives us a good idea of what the park is supplying so that we do not toast the Air conditioners.

" My own preference would be to operate only one hot leg by shutting the other one off with the breaker on the post. Try each breaker and you will know which one powers the circuits you want. However, those type hookups often have 30 amp wiring, so don't operate too many appliances at once...."

FWIW: I wired an RV Park several years ago and this plan was typical: One pair of wires (A & B) with a neutral and a ground, protected by a 200 amp main breaker, go to each pedestal of a group. Alternate sites had A as the primary; it supplied the 30 and 20 amp receptacles, plus half (120v) of the 50 amp receptacle (A & B). The pedestal had, of course, three breakers: A 30, a 20, and a double-pole single-throw 50. Every other site had B as the primary. In theory, this split the 240 service exactly in half. If you were the only camper in your group using 50 amp service (everyone else using 30 or 20) you'd still be getting a diluted circuit, whether it was "A" or "B".

When you use 30 amps towerguy you loose a lot of power you can only run one a/c at a time U have to I belive shut the a/c down that you are using to run the microwave but you can go to camping world and get a devive that will allow you to run a 50 amps setting it has a 30 amp plug and a 110 volt plug on it that you plug into your shore box and then the attchment peace has a 50 amp setting in side it and you can then have 50 amps all together but you need to go to a camping world store for it I have one for my coach it works great I love it if you have any questions please post it here

Sincerely

Diana

The cheater box gives you a total of 50 amp at 120vac. A true 50 amp circuit gives you a total of 100 amps at 120vac. You need to measure your pole first as some are wired with one phase on the 30 and the other phase on the 20 amp service and some are wired as noted in previous post. I have found all federal parks wired with the two services out of phase for a total of 240vac.

In passing I should mention that if you have a 50 to 30 amp pigtail you have 50 amps available on your 30 amps cable and then you can run both a/c at the same time.

When I did my bus conversion back in the 90's I wired it for 30 amp with the ability to quickly change to 50 amp. However, I also ran the rear a/c power line down into the bay where I had a plug/jack and then back to the breaker panel. I could split the circuit and attach a extension cord (12 gauge) to run the rear a/c. This I plugged into 20 amp circuit. If you find the 20 and 30 are in phase (not 240vac) then there may only be a total of 30 amp wired to the power post and over loading it will cause a lot of heat which may cause a sharp drop in voltage.

We have used a cheater box to get 240vac in our Newell so we could run the washer and dryer. In our Barth I rewired for 30 amp service with a load sharing inverter (Zantrex 458) that is suppose to kick on if we need extra amps. So far not working that way (yet).