Crack Down on 50 Amp Rigs Using 30 Amp Sites
I don't know how long this has been going on but I learned today that some RV parks including the Washington/Pittsbugh KOA I had booked has a policy that if your rig has 50 amp service, you can't use ...
Forum Discussion
The campground owner has a legitimate issue he is addressing even if he has an up to date electrical system.
- Your average 30amp RV is not pulling 30amps other than for a couple seconds when the air/con starts the compressor and then it drops way back. Our continuous load with air/con, TV and a couple other minor loads is around 15amps.
- The 30amp rating is not a continuous rating. Continuous, your 30amp pedestal is only good for 24amps.
- A string of 10 30amp pedestals won't be supplied with a 300amp circuit. The code is set up to account for the fact that it is unusual for every pedestal to be running at 30amps at the same time, so they legitimately allow the upstream circuit to be derated...maybe something like 200amps (I would have to look it up for an exact)
Now the problem with 50amp units...
- Particularly the newer ones have systems that track the consumption and run up to the 24/30amp max. Even though you aren't using more than the pedestal is rated for, you are adding 10-15amps more than a typical 30amp rig would consume and what is built into the upstream breakers design assumptions.
- Allowing people to say they won't use more power is impossible to police and will just make for angry customers when you do.
So what happens: Let's say it is a 200amp circuit feeding 10 30amp pedestals.
- 10 30amp rigs each averaging 15 amps on a hot night...The average pull is 150amps and there is enough overhead on the main circuit that as long as you don't have multiple air/con units kick on simultaneously, it can absorb the startup loads for the air/con compressors.
- 5 30amp rigs and 5 50amp rigs using load shedding systems to keep the load at 25amps. That's 75amps for the 30amp rigs and 125amps for the 50amp rigs...total 200amps...sounds like it should be OK...not really. First time someones air/con compressor kicks over, the surge will push you over 200amps and the upstream breaker pops...now you have 10 customers ticked off because it's 2am and it takes a half hour for your on call person to get dressed, drive down to the park, unlock the master panel and flip the switch...only to have it repeat in a 1/2 hr.
I've simplified a few issues but this is very much a legitimate issue.
- Your average 30amp RV is not pulling 30amps other than for a couple seconds when the air/con starts the compressor and then it drops way back. Our continuous load with air/con, TV and a couple other minor loads is around 15amps.
- The 30amp rating is not a continuous rating. Continuous, your 30amp pedestal is only good for 24amps.
- A string of 10 30amp pedestals won't be supplied with a 300amp circuit. The code is set up to account for the fact that it is unusual for every pedestal to be running at 30amps at the same time, so they legitimately allow the upstream circuit to be derated...maybe something like 200amps (I would have to look it up for an exact)
Now the problem with 50amp units...
- Particularly the newer ones have systems that track the consumption and run up to the 24/30amp max. Even though you aren't using more than the pedestal is rated for, you are adding 10-15amps more than a typical 30amp rig would consume and what is built into the upstream breakers design assumptions.
- Allowing people to say they won't use more power is impossible to police and will just make for angry customers when you do.
So what happens: Let's say it is a 200amp circuit feeding 10 30amp pedestals.
- 10 30amp rigs each averaging 15 amps on a hot night...The average pull is 150amps and there is enough overhead on the main circuit that as long as you don't have multiple air/con units kick on simultaneously, it can absorb the startup loads for the air/con compressors.
- 5 30amp rigs and 5 50amp rigs using load shedding systems to keep the load at 25amps. That's 75amps for the 30amp rigs and 125amps for the 50amp rigs...total 200amps...sounds like it should be OK...not really. First time someones air/con compressor kicks over, the surge will push you over 200amps and the upstream breaker pops...now you have 10 customers ticked off because it's 2am and it takes a half hour for your on call person to get dressed, drive down to the park, unlock the master panel and flip the switch...only to have it repeat in a 1/2 hr.
I've simplified a few issues but this is very much a legitimate issue.
