wapiticountry wrote:
msmith1.wa wrote:
Let me start this off by stating I own an EV, but it is not used by us when we RV, because we use a truck and trailer.
Why is it incumbent on the park to provide charging stations?
The charger that I have at my house I would call semiportable, it is kind of big, but it can be done. It plugs into the same outlet that a 50 amp RV would. I bought this version because if we were to travel with the car, some places have thus type of plug that they allow guests/customers to use for charging.
This is a big if, but if the power pedestal is wired properly it should be able to supply power to all of the plugs at their rated capacity. With appropriate adapters, when needed, both the RV and EV could be connected to the pedestal. One to the 50 and the other to the 30 if the pedestal is equipped with both a 50 and 30. If not, one to the 30 and the other to the 15.
I know this doesn't typically apply to a motorhome and toad combination, but most parks charge an extra vehicle fee. The park could just charge an EV fee in attempt to cover the added electricity use. Or the less popular option, raise the price for all sites.
All NEC code requirements take into account what is called "demand factor". What that means in simple terms is only a percentage of the available power on any circuit is used at any given time. That is why if you add up the breakers in your home panel you get a value much higher than the rating for the panel. The NEC wiring codes take into account the fact you never use all the circuits at the same time or at maximum draw. However if you were to somehow use each of those home circuits at their maximum rating you will trip the main breakers even though you didn't overload any individual branch circuit. Same with a loop of power pedestals in a RV park.
Current code allows for up to 8 50 amp RV pedestals on a 200 amp circuit. That is because the demand factor for 8 RVs on 50 amp pedestals on a loop is less than 50%. That means that at peak usage times if there are 8 RVs on that loop they will have an average draw of less than 25 Amps per each leg of that 240 volt, 50 amp pedestal (6000 Watts). The demand factor is computed using historical data of power usage by RVs. The demand factor calculations were not computed taking electrical vehicle charging into account.
A single Tesla using the Tesla 50 amp power cord draws 32 Amps per leg ( 7680 Watts) and will draw that continuously until the Tesla is charged, which could be up to 10+ hours. To put it in other words, that single Tesla charging is taking more power than the average RV consumes during peak usage times. Just like you couldn't add a 9th RV and pedestal on that 200 amp loop or run all your circuits in your house at maximum rating, you can't add EV charging without overloading the main circuit and tripping the breakers that serve the entire loop.
Good reason for adding a few dedicated J1772 units on dedicated circuits not on any loop.
