Metered RV Pedestal

[StephenSDH]

I see they sell metered RV Pedestals for campgrounds. I have never RV'd in my life.

Is it common for RV Pedestals to have a meter on it?

I assume it is customer owned meter and has nothing to do with the utility.?

I assume a camp ground worker walks around and writes down what the RV used for the day/week/month and bills the RV'r accordingly?

Anyone have experence with this?

 

[hurk27]

I do a few Jelly Stones parks around here and yes they own their own site meters and bill customers for duration of stay when less then a month or monthly when longer, these meters have to be certified by state, in our case Indiana weights & measurements, most of these parks will have primary metering out by the road, and all MV and LV wiring after this point is maintained by the owner of the park, while some smaller parks will have LV metering at a central location, 551 and 552 of the NEC will cover them as for requirements.

To add the reading of the meters can be manually or if set up for it, done remotely depending upon the type installed, we have both radio, and electronic cat-5 connected ones, as well as common mechanical ones.

 

[StephenSDH]

Thanks your reply was very helpful.

I have a design job that it sounds like I will get to design a 200 site RV park with all 50A pedestals. I am guessing they will want to meter it since it would probably be around $3-6 dollars per RV per day for electrical.

I was wondering about meters w/ radio. I will have to look into the radio option when I get to that point.

Thanks, Steve

 

[hurk27]

Thanks your reply was very helpful.

I have a design job that it sounds like I will get to design a 200 site RV park with all 50A pedestals. I am guessing they will want to meter it since it would probably be around $3-6 dollars per RV per day for electrical.

I was wondering about meters w/ radio. I will have to look into the radio option when I get to that point.

Thanks, Steve

You might want to look at 551.71, you will need at least 70% of the spaces to also have 120v/30 amp receptacle.

 

[StephenSDH]

The pedestals I have been looking at have a 120/240 50A Recept, 120V 30A Recept, and a 120V 20A GFCI Recept.

From doing the load calcs. There is no good way to feed these pedestals. I am looking at having a 120/208 service. With the 9.6 KVA per hookup it looks like the most economical way is to tap 5 pedestals off a 150A feed.

Should be an interested design project. I know the customer has no idea how large the service is going to end up being. Should be fun to break the news to them $$.

 

[hurk27]

We do #2224 URD on 100 amp, with 4 pedestals per circuit, we alternate the 30a and the 20 amp every other pedestal per phase, larger wire cost can kill a job, Midwest is about the most cost effective for these pedestals. 5 pedestals per circuit will leave you with an imbalance, you will get very few 50 amp RV's in a park, although they are getting more popular.

 

[StephenSDH]

We do #2224 URD on 100 amp, with 4 pedestals per circuit, we alternate the 30a and the 20 amp every other pedestal per phase, larger wire cost can kill a job, Midwest is about the most cost effective for these pedestals. 5 pedestals per circuit will leave you with an imbalance, you will get very few 50 amp RV's in a park, although they are getting more popular.

Is there a reason you don't put more then 4 on a circuit? Using 3600VA from 551.73(A) it looks like you could get up to 12 on a circuit. I think with #2 aluminum you would need to have it on a 90A breaker. I feel like I am missing something.

12 Pedestals x 3600va / 240v * .5 demand factor = 90a

Everything I have read points to Midwest being the best product and price.

I was wondering how many RV's will be 50A. I have a feeling the owner will trim back on making them all 50A 240V Pedestals. It would be nice to make them all 50A, but the cost seems to make it unreasonable.

Thanks again for the help.

Steve

 

[haskindm]

The pedestals I have been looking at have a 120/240 50A Recept, 120V 30A Recept, and a 120V 20A GFCI Recept.

From doing the load calcs. There is no good way to feed these pedestals. I am looking at having a 120/208 service. With the 9.6 KVA per hookup it looks like the most economical way is to tap 5 pedestals off a 150A feed.

Should be an interested design project. I know the customer has no idea how large the service is going to end up being. Should be fun to break the news to them $$.

How are you going to supply the 240 volts of a 120/240 volt 50-amp receptacle form a 208 volt service?

 

[StephenSDH]

How are you going to supply the 240 volts of a 120/240 volt 50-amp receptacle form a 208 volt service?

They would be 120/208 50A, which is allowed.

 

[hurk27]

Is there a reason you don't put more then 4 on a circuit? Using 3600VA from 551.73(A) it looks like you could get up to 12 on a circuit. I think with #2 aluminum you would need to have it on a 90A breaker. I feel like I am missing something.

12 Pedestals x 3600va / 240v * .5 demand factor = 90a

Everything I have read points to Midwest being the best product and price.

I was wondering how many RV's will be 50A. I have a feeling the owner will trim back on making them all 50A 240V Pedestals. It would be nice to make them all 50A, but the cost seems to make it unreasonable.

Thanks again for the help.

Steve

Because we had allot of problems under feeding RVs around here, the weekend warriors flood these parks and on holidays they are packed, the NEC code minimum just don't cut it, it might be different in your location but I would do some research before making this determination.

They would be 120/208 50A, which is allowed.

Most RV's are designed for 240 volts, for this reason we avoided 208, while some AC units in them will run on 208, you have no room for voltage drop, which is a big problem in a large park, most of our parks have comfort stations at various locations, each one has a 7200 volt fed single phase transformer feeding a single phase MDP each MDP has 12-24 100 amp breakers for the pedestals in them and also the breakers for the comfort station and street lights.

 

[haskindm]

They would be 120/208 50A, which is allowed.

That is true as long as all of the loads in the RV are actually 120-volts divided over the two legs of a 120/240 or 120/208 volt service. Now that 50-amp 240 volt power is readily available many RV's are using 240 volt appliances (such as stack washer and driers). If you connect these appliances to a 208-volt source, at best you will have unhappy campers because their appliances take a long time to heat up. At worst you are violating the UL listing unless the appliances are listed for both 240 and 208 volt operation. If they are motor loads, the motor may be damaged due to low voltage, especially during periods of peak usage when voltage drop may be exaggerated.
I would refer you to this thread regarding marinas (boats have similar wiring needs to RV's). The consensus is that 208-volt wiring is not acceptable.
http://forums.mikeholt.com/archive/index.php/t-53101.html

 

[StephenSDH]

That is true as long as all of the loads in the RV are actually 120-volts divided over the two legs of a 120/240 or 120/208 volt service. Now that 50-amp 240 volt power is readily available many RV's are using 240 volt appliances (such as stack washer and driers). If you connect these appliances to a 208-volt source, at best you will have unhappy campers because their appliances take a long time to heat up. At worst you are violating the UL listing unless the appliances are listed for both 240 and 208 volt operation. If they are motor loads, the motor may be damaged due to low voltage, especially during periods of peak usage when voltage drop may be exaggerated.
I would refer you to this thread regarding marinas (boats have similar wiring needs to RV's). The consensus is that 208-volt wiring is not acceptable.
http://forums.mikeholt.com/archive/index.php/t-53101.html

NEC 551.40(A) "Electrical Equipment Connected Line to Line shall have a voltage rating of 208-230 volts."

I agree with you I would perfer to have 240V power at the pedestals. From the perspective of designing the distribution system it would require several 1-phase 240V transformers fed from a 3 phase service adding both cost and transformer losses. From my reading there are not alot of L-L loads in an RV, and if there are they are rated for 208V. I read 555 for Marina power and 208 50A is not allowed.