Pulling more than 50 amps ?

Reisender wrote:
In practical terms on a 50 amp pedestal you can draw 40 amps st 240 volts continually. We have an electric car and we sometimes do that.

Real world experience. Visiting a friend with a Newell with three AC’s, all running as well as a bunch of other things. Our Electric vehicle hooked up to his pedastal via a Y connector off the box pulling16 amps at 240. No problem.

Yes, 40A at 240V is correct and possible, that is 9600W draw.

50A at 240 is 12,000W.

However, what most folks seem to miss is a RV "50A" connection IS actually a COMBINATION connection, it is a 120V/240V connection, it has a NEUTRAL which allows for not only 240V appliances but 120V appliances also.

This means you can use a combination of 120V AND 240V appliances on this connection.

Pure 240V ONLY devices do not need and are not wired for the Neutral.

Home water heaters, deep well water pumps, heavy duty air compressors, high BTU home A/C units typically fall into the category of 240V ONLY.

Your high amperage car charger is is using BOTH the hot legs (L1 and L2) and not the neutral so it is subject to BOTH of those breakers limits which is 50A or 12,000W and would fall into the pure 240V only category.

Now, for 120V loads, you use only ONE of the Lines coming in (L1 OR L2) PLUS THE NEUTRAL and you can draw a max of 6,000W at 120V (50A).

With 50A 120/240 service you actually have the same as TWO 50A at 120V (6,000W) power feeds. In reality you could say that for 120V appliances you actually you have up to 100A of capacity (12,000W).

You however cannot "combine or connect" L1 and L2 together because they are out of phase (one positive and one negative going). Adding two voltages out of phase CANCELS the voltage and in this case creates a huge short and the result would be zero volts.

Typical RV 50A 120/240 will put MOST of the loads on the L1 "leg" and very few loads on the L2 leg. L2 on the RV is often reserved for the second or third AC unit.

It is done this way to allow a 50A RV to hook up to a 120V ONLY 15A-30A pedestal and have MOST of the RV get power although at very limited amperage of course.