Correct voltage for 50 amp service

Anything that set off my low voltage AC detector at 15> feet always got my attention.

Work safe. Gloves, plastic overshoes, safety goggles, no jewelry, and NO DISTRACTIONS, are a must.

Chop power to the circuit before working on it. TRIPLE check all made-up connections.

Toolguy5 wrote:
Sorry to have started this debate.

I now understand why there is so much confusion. The panel in your house the breakers are alternating lines. The panel in the RV is split.

Agree that some are like yours, split with the main breaker in the center and one hot leg on the left and the other on the right. But there are also some like mine with the main breaker on the end and the breakers alternating on the hot legs just like a house. In my case, I could install a linked double pole breaker in two adjacent slots and have 240 vac if I wanted to install say a 240 vac clothes dryer.

LScamper wrote:
road-runner,
That was not the best example of working on a live system! Before OSHA, the two and three man rules and all the safety regulations that came along it was one hand in the pocket. Measuring voltages on live 480V stuff always scared me. Connecting grounding hooks on high voltage equipment was alway exciting.

^^^^^ Exactly, Fast forward to today's world and its a zero energy policy,lock out/ tag out and the proper arc flash ppe for the system you're working on.I have seen way too many video's on arc flash burns.
Oh, and I would seriously fire the person who trimmed out that panel!

road-runner,
That was not the best example of working on a live system! Before OSHA, the two and three man rules and all the safety regulations that came along it was one hand in the pocket. Measuring voltages on live 480V stuff always scared me. Connecting grounding hooks on high voltage equipment was alway exciting.

LScamper wrote:
This may help understand this phase stuff.

Phase definition

Good video, and I agree with everything he said (Except about not being able to call your dog a goldfish. In today's political environment, you could get into big trouble objecting to that!).

However, I sure don't agree with how he was poking his hands into the live breaker box, and waving his arms around. I was stressed out thinking he'd fry himself before the video was finished. And I'd have a hard time trusting those alligator clip covers when connecting to a live circuit like he did. Gave me shivers just watching.

This may help understand this phase stuff.

Phase definition

is L1 always on the left? Is L1 always the top tap?

myredracer wrote:

Also, it is incorrect to use the term "phase" when it comes to 120/240 volt services and the designation for each hot leg.

I just don't understand why it's not obvious that there are multiple equally valid ways to view and describe the 120/240 volt service. What if the power is being produced by two 120 volt inverters, or two synchronized 120 volt generators? You better be concerned with the phases when you hook them up, or sparks will fly. I think the safest way to communicate this service is using the term split phase. Then grid-centric and transformer-centric people can think of it as single phase (or no phase, I guess), and electronics types can think of it as two phase, and everybody would still be able to communicate what type of service they're thinking about without having to debate the "correct" way to look at it.

What??? Is this how they do things in Mexico?

Slight Problemo Amigo


It is spelled r-e-g-u-l-a-t-i-o-n-s

Comision Federal de Electricidad

Delta wound transformers are allowed only for Industrial Accounts. Not just commercial accounts but industrial accounts. I should have pointed that out. THEN C.F.E. tells the business what size transformer is allowed. For the park I was allowed 20 Kw. Meaning 4170 vac input and 254 volt output (tres hilos mas neutral) Three phases plus neutral.

They blanched at the thought of me installing a transformer and tickler to make a Scott Connection 3-phase to single phase plus neutral.

As I thought, the view sites and the shade sites had the highest occupancy percentages and thus all three phases were used for the 9 sites. The hotel and my casita were fed from the least of the phases because there wasn't any air conditioners or large pumps involved.

The place is in ruins now, abandoned with no services. I sold the transformer to a large truck repair shop in Guacamayas and gained a whole (something-like) sixty dollars on the deal.

Mexico went to digital demand meters in 2000 in our area for 3 phase and then in 2011 for dos hilos 254 volt service. For our freezer use the family will never voluntarily surrender our analog meters.

Toolguy5 wrote:
Sorry to have started this debate.

I now understand why there is so much confusion. The panel in your house the breakers are alternating lines. The panel in the RV is split.

The panel in your house and a 50 amp panel in an RV are exactly the same except one is rated 50 amps and the one in the house is 200 amps (or possibly 100 amps or other rating). Except for current rating, zero difference. Most breakers are even interchangeable.

Note that the industry standard service voltages are 120 volts and 240 volts, not 110, 115, 117 volts or 220 or 230 volts or any other voltage. Providing that there is no voltage drop on the power company system or the service drop into a house or anywhere downstream of the main panel, the voltages should be 120 and 240 volts with no loads connected/running. An explanation of ANSI standard C84.1 and voltage tolerance boundary can be found here. Appliances and equipment however can have nameplate voltages other than 120 or 240 volts.

Also, it is incorrect to use the term "phase" when it comes to 120/240 volt services and the designation for each hot leg. The neutral is located exactly 1/2 way between each leg of the 240 volt hot conductors so you get 120 volts in reference to each of the two hot legs. A 120/240 volt service is termed "single phase". "Phase" is a term normally used in 3-phase power systems because there are 3 hot legs each 120 degrees out of phase in reference to the other 2 hot legs (there can be a neutral ("wye")or no neutral ("delta")).

RV parks are occasionally connected to 3-phase systems and have 120/208 volts with 208 volts between the two hot legs. Since most 50 amp RVs don't have 240 volt rated appliances, most will not notice. I'm pretty certain anyone working on any 3-phase derived system has to be a properly licensed electrician, unlike in 120/240 volt CGs where any monkey can work on the systems/components for maintenance.