Campsite Breakers

[JMod45]

I just got home from a weekend camping, and had an issue with the 30 amp campsite breaker tripping. I've had this issue a few times before, and wondering what I could do to prevent it.

I have a 15,000 BTU air conditioner that I had to leave on low, and switch my water heater to propane to reduce the strain on the system.

I have been shutting off the ac when I run the microwave at most sites I go to. Should a 30 amp outlet be able to run a microwave and ac unit at the same time?

I saw an adapter at an RV store in town last week that made a 50 amp circuit from a 30 and a 20. Which made me start thinking about something similar for my 30 amp trailer.

I read about the "cheater boxes" a little bit, and I do know a little about electricity. I know these adapters don't provide a true 50 amp service, and you can't have any GFCI plugs (this site has GFCI). If I used one, and then a 50 to 30 adapter, I'm just killing one leg, which if I understand the boxes correctly, then I would be running off just of a 30 amp plug (possibly 20) with a lot of extra wiring in the way.

So for you electrical experts; Is there a way to use the 20 amp plug along with the 30 to get a little more amperage without increasing the voltage so I'm not tripping breakers when running the ac? I'm pretty sure I don't need more than 30 amps, but with some of these campsite breakers, I feel like it may be tripping closer to 20 due to the age of them.

[Finance]

You might have some success using an extension cord to run from the 20 directly to your kitchen and unplug the MW from the coach and use the cord.

It’s also quite possible the builder ran only 30 amps to the site, and the 20 is almost certainly just parallel to the 30 amp breaker. In which case you’ll trip the breaker back at the main panel and need assistance to restore power. Alternatively it could be fed from a larger breaker looped through several campsites.

Or you could hit the jackpot and it’s a 50 amp 240v feed with a 30 and 20 at your end. Really no way to know without some investigation.

[JMod45]

Originally Posted by Finance

You might have some success using an extension cord to run from the 20 directly to your kitchen and unplug the MW from the coach and use the cord.

It’s also quite possible the builder ran only 30 amps to the site, and the 20 is almost certainly just parallel to the 30 amp breaker. In which case you’ll trip the breaker back at the main panel and need assistance to restore power. Alternatively it could be fed from a larger breaker looped through several campsites.

Or you could hit the jackpot and it’s a 50 amp 240v feed with a 30 and 20 at your end. Really no way to know without some investigation.

I didn't think about the whole site being 30 amp, so any tricks could trip main breakers.

My issue was the breaker at the site kept tripping when I first hooked up. Only thing on was AC and water heater. Turned AC fan down to low, and switched water heater to gas, and it didn't trip anymore.

I was originally thinking that the AC alone was tripping a 30 amp breaker, but since the breaker inside the trailer is a 20 amp, that would mean the site 30 was weak and tripping below 20. Then I remembered the little switch on the water heater. I didn't think that would pull a whole lot, but I am going to look into it.

Turning off the AC for a couple of minutes to run the microwave isn't a big enough issue for me to worry about, just not sure if that is common for 30 amp trailers.

[twinboat]

I have a 30amp RV and run the AC and microwave without tripping breakers. The converter/charger and fridge is also on 120 power. Water heater is gas only.

Running the AC on low only drops the amp draw slightly. The compressor, which draws the most current, still operates at full power. Its possable that the coils on the roof are dirty. That can significantly increases amp draw on the unit.

If your batteries are old and weak, that can cause the converter to draw more amps, adding to the problem.

A 30/20 cheater adaptor will do nothing for you. They are for 50 amp RVs, trying to suck a bit more power from a 30 amp plug. Remember real 50 amp service is 50 amps on 2 legs for the capabilities of 100 amps of 120 volt stuff running. The cheater is 1/2 that and only if used on a 240 volt 50 amp RV.

A 50 amp down to 30 amp adaptor can help because you are now using one side of the double 50 amp breaker outside. You still have a 30 amp main breaker inside that will trip if overloaded but you need to be at a 50 amp site.

[schad]

I have a TT with 30A service. The 15k BTU A/C is almost always running, and we've run it with the fridge and microwave or electric water heater (or both) dozens of times. We've never tripped a breaker.

If you can't run your A/C and anything else, I feel that something is wrong. Maybe low voltage at the park causing your appliances to work too hard, or your A/C is in need of maintenance/TLC. There could also be wiring problems that only manifest when the wires warm up due to load.

[egwilly]

My quess is that if the park is full, you are probably not seeing the full 30 amp service to the pedestal. 30 amp is only one leg of 120 VAC at best.

Most of the parks are chained wired thru several pedestals in one area. So, more loads along the line reduce the amount you receive. In some cases, if you are the first site on the chain, then everything is fine.

I wouldn't assume there is something amiss with your trailer, but I would install a meter to see the actual voltage supplied. I have seen ours drop 10-15volts when everyone is running high demand equipment.

[Gary RVRoamer]

So for you electrical experts; Is there a way to use the 20 amp plug along with the 30 to get a little more amperage without increasing the voltage so I'm not tripping breakers when running the ac?

Short answer: No. No magic way to combine 30 & 20 to get more power to a 30A RV. Besides, your RV has its own 30A breaker that would trip if exceeded. Those "cheater" cords/boxes can sometimes help a 50A RV get more power from a 30A pedestal, but are of no help when the RV itself is limited to 30A.

Operating an a/c and a microwave simultaneously on 30A power is a very marginal situation. Some rigs my manage it some of the time, but it's a typically touch & go situation. A newer a/c in good condition and a relatively small microwave can work a long as park power is solid, but it doesn't take much to go over the limit.

An a/c requires about 12 amps when the compressor is on but nearly double that each time the compressor cycles from off to on. If you can get it started and it's hot enough that the a/c compressor never shuts off, you have a fair chance of using other appliances at the same time. Another factor is that the other appliances also probably have thermostats, e.g. fridge or water heater, so they also cycle on and off. At any given moment, all of them, some of them, or none of them may be drawing much power. Things might run great for an hour or two and then suddenly a breaker trips because they all tried to cycle on at the same time.

In some campgrounds the available power is limited as well. If the park voltage falls below 120v, the amperage drawn by your appliances increases to compensate. Down around 105-110v, that increase gets significant. It's not unusual in older parks for the voltage to drop to 105 or less when everybody has their a/c on.


Last, a 30A outlet & pedestal is rated for a 30A peak load but not a sustained (more than 30 minutes) 30A. It may get hot enough with a sustained 25-30A load to trip its breaker. Testing standards for the ratings allow sustained load to be 80% of the peak, so it's common for breakers and outlets to get overheated anywhere above 24A (80% x 30A).

[Orion7594]

Pure and simple, the campground's breaker is weak. You should be able to run anything in your trailer in any combination and not draw over 30 amps. Have had a weak campground breaker a couple of times and having campground change it fixed the problem. Realize breakers aren't designed to be out in the elements.

[KanzKran]

That roof A/C may have a rated current draw of 16A or so at rated voltage (from a Dometic data sheet, with compressor and fan combined), and the water heater may be as high as 1440W (12A at 120V), which totals 28A or more. Drop the voltage and the A/C unit will draw more current, thought the water heater will draw less. But that's still a high current draw for a 30A feeder.

Locked-rotor current for that compressor could easily reach 70A, by the way, and that includes start-up, since the rotor is stationary when first energized. Circuit breakers are designed to handle overloads, with small overloads tolerated for long periods (potentially hours) and large overloads for only a short time (inverse-time thermal trigger), and very high overloads tripping out almost instantly via a magnetic trigger (like 8-10 times the breaker's rating).

It's likely that you're flying too close to the sun with both water heater and A/C unit on concurrently, and maybe also with a battery charger and other loads on, too. An older breaker may also be tripping at a lower threshold.

A soft-start or hard-start kit might help with A/C start-up surge current and time, especially in low voltage conditions.

[MrsSquid]

A worn out breaker was the culprit for us this past weekend. We threw the breaker several times the first day hooked up. After verifying that our systems were fine, my husband called the campground office and told them that he thought they'd have to replace the breaker.

To their credit, they didn't question my husband's knowledge and promptly replaced the breaker. We didn't have any more issues for the weekend, even with running all the ACs in the ugly hot temperatures.

[TXiceman]

Breakers age as they get older, they will trip early. Also, low voltage at the pedestal will increase the amp draw on inductive loads like the A/C unit. Put the watr heater and fridge on gas and lessen your electrical load.

Invest in a Progressive Ind EMS and you can see the volts and amps to your rig.

Ken

[jacwjames]

Originally Posted by TXiceman

Invest in a Progressive Ind EMS and you can see the volts and amps to your rig.

Ken

You might invest in a Progressive surge protector, I installed a 50 amp one on my coach and besides protecting the coach for poor quality power it also displays the amps & volts. I purchased the extra display so I can monitor inside the coach. If there was a problem with low voltage the surge protector would protect the coach.

I had a Class C and don't ever remember kicking the 30 amp breaker. We could even run the AC on a 20 amp breaker if we shut everything else off.

It almost seems like your AC may be pulling too many amps. My front AC was starting to pull high amps and found the motor was almost seized up.

[JMod45]

Dang, this is a busy forum first thing in the morning.


I guess I should have mentioned, my trailer is roughly 4 months old (bought new at the very end of March), so everything is still clean, and in working order.

I've had the site breaker trip at one location when I ran the microwave for more than 30 seconds with the AC running and electric water heater switch on. That place was completely booked up, and every spot was filled, so there is a decent chance the voltage was lower than optimal. The site looked pretty well maintained though, so the wiring was probably all in good shape.


On this outing, we got the trailer parked, plugged in power, started the AC, and within about 2-3 minutes, the site breaker would trip. This happened twice before I remembered the water heater switch, put the AC fan on low, and shut all the lights off inside. I realize the low/high on the fan is a minimal change, and all the lights are LED, but it was about 95 degrees outside, so wanted to give the AC everything I could. I let the breaker cool down for about a minute before turning it on the last time, as it was fairly warm.



There was only about 4 other trailers, the place was mostly empty. I was at the end, and other than the host across from me, my closest neighbor was 5 sites away. I don't think we were taxing the parks system at all. It would not surprise me if there was less than 120 at the plug, I did notice what looked like the main breaker panel for all of the sites was at the other end from where we were parked. This is in a forest, so the wire has a pretty long run to get there, which could definitely drop some voltage.


I completely forgot that lowering the voltage increases the amperage. I keep a volt meter with me all the time, so I could have easily checked it. I'll keep that in mind next time I go out. I'm thinking I may start using the 50 amp plug if the site has one, so I don't have to worry about what I turn on inside. I already have a 50 amp to 30 amp adapter, and have a 30 amp surge protector that I always use.


After seeing the cheater box adapter, I got excited that it may be possible to have a little bit extra amps using both plugs, so thought I would ask. I realize that is not the case now.



The park is clean, and is a nice quiet getaway only a few hours from home, but maintenance on stuff like breakers, and water hookups probably isn't the best. I'm not sure the on-site staff is skilled enough to change a breaker, and didn't want to test them while I was there. I will likely e-mail the park, and see if they could have a maintenance person check that breaker now that I am not there.


Thank you to everyone for the input, it is definitely helpful.

[Spdracr39]

Originally Posted by Orion7594

You should be able to run anything in your trailer in any combination and not draw over 30 amps.

This is totally and completely untrue. The total amp draw of all major appliances running at the same time is around 45 amps. Not gonna happen on a 30 amp rv.