awesome, thanks Josh.
No problem Allen, I'm glad to help when I can.
I was unsure about the 50 or 100 amp breaker as I've been told different things regarding their total rating... Most of what I've read has said that a double (any size) breaker is still the same size but just 240 volts. Say a double 50A breaker is still MAX a 50A breaker but now it's 240v vs 120v, is that not correct?
In this application it is correct to use a "50A dual pole 240V" breaker. This will provide two hot legs with 50A available for each. If either is overloaded, the whole breaker will shut off. This is because you are providing a single circuit that would be described as "single phase 50A 240V 4-wire" indicating that there is one circuit that has two hot legs, a neutral, and a ground. Usually these kinds of circuits are used for 240VAC loads (like ranges or dryers) that have a 240V heating element in them. In these situations most of the load is balanced across the 240V hot legs. However, this is no different than supplying a sub-panel, which is what we are doing in this case. BUT, in this case, the load is not necessarily balanced between the two hot legs because we are breaking that service down into six 20A 120V circuits. So, some attention should be paid to be sure to balance your heavy loads between the two hot legs, rather than loading them all up on one side. You do have 100A of total capacity available at the Distro, but it is split up as 50A from each of the hot legs. So, balance your heavy drawing devices on each side of the service coming in and you can make the most from your available power source.
This is the part that I'm still very unclear on, which is true?:
A. A double 50A breaker has a 50A TOTAL capacity and if either leg of the breakers exceeds that 50A it will trip
B. A double 50A breaker has a 100A TOTAL capacity with each leg capable of 50A and if either breaker exceeds 50A, or a total of 100A between the entire breaker, it will trip
C. Something completely different?
is the closest to correct, BUT not completely correct. You essentially have two circuits with 50A available on each circuit. The Distro takes each of those circuits and distributes them to THREE 20A duplex outlets on the back of the unit via the circuit breakers on the front panel of the unit. When EITHER of the two circuits exceeds 50A the breaker will trip, there is no option of "or a total of 100A between the entire breaker".
So with a double 50 breaker, breaker handles up to 50 amps and then would also power one of the two "hot" legs of the feeder cable, correct?
Yes. 50A per hot leg.
Now isn't the risk with a double breaker that if somehow you overload one leg the entire breaker will trip?
Yes, that is an issue that you need to be aware of.
Wouldn't it be better to run 2 independant 50 amp breakers but just make sure they're "stacked" or on opposite legs?
Yes, you could do this in a different situation, but NOT in this specific situation. In this situation you are providing one circuit that is 240V with a current carrying capacity of 50A. According to our national electric code, when you are providing a 240V circuit from a panel in the specific manner we have been discussing in this thread, you MUST tie the breaker handles together. If you wanted to provide two separate 120V 50A circuits, then each circuit MUST HAVE its own neutral. So, you would have to run two hots, two neutrals and a ground from the panel to the Distro. This will require a minimum of 5 conductors, AND you can NOT tie the neutrals together inside the distro, they MUST be kept separate! So, you will end up with a bunch of "non-standard" plugs, cables, and interconnects. This gets expensive and heavy quickly with the extra copper required by the additional neutral.
I can also see it being beneficial when there may not be 2 open slots together.. Maybe not, just kind of thinking out loud..
Sure, it is handy to do, but it will not meet code if you were to get inspected.
So your set up is like this? (are you using the standard straight blade stove plug?)
Double 50A breaker to a box with a 50A female stove receptical in a box - 50' cable with male stove plug on one end and a female stove plug on the other - male 50A stove plug wired directly to your distro for 100A of 120 single phase?
Yes. Exactly. Stove plugs are relatively cheap and they make good connections. Since they are almost always a right angle plug and receptacle, It is easy to wrap a big heavy duty zip tie around the mated connectors to help insure that they will NOT inadvertently come unplugged unexpectedly.
What gauge of cable are you using? Are you using a multi conductor cable say like a 6/4?
Yes, exactly again! 6 AWG, 4 conductor SOOW.
I'd prefer a twist lock type of connecter to avoid or at least reduce accidental unplugging, wouldn't the connectors below work? Except I can't seem to find them available anywhere..
Sure, twist lock connectors are great to use, but I'm not a big fan of the standard Hubble twist lock connectors because the blades on the male ends will often get bent and eventually break off. Also, the electrical industry has not really accepted the NEMA 50A 240V twist lock standard. Instead you should look up the Hubble "California Connector" on the internet. Specific part numbers include:
CS6365 - Male Cord Mount Plug
CS6364 - Female Cord Mount Receptacle
CS6369 - Female Panel Mount Receptacle
CS6375 - Male Panel Mount Plug
These are the typical 50A 240V twist lock connectors that you will find on a larger commercial type generator, so even if you are using the NEMA 14-50 straight blade connectors in your system, you should still have an adapter cable with a CS8265C plug to a NEMA 14-50R receptacle. (I don't currently have one, but I'll probably need to make one up in the near future.) Also, you will note that the contacts on the male connectors are protected from being beaten and bent, unlike the 20A and 30A versions of the standard Hubble Twist-Lock connectors are. These are great connectors, to be sure... but at around or more than $100 each, they had better be!
Good luck out there and be safe! Remember, if you don't understand what you are doing, DON'T DO IT! Advice you receive from people on the internet is usually what you paid for it... NOTHING! Do NOT experiment with electricity, it is a great way to end up DEAD if you don't know what you are doing. DO NOT take any of the discussion above as fact. Check with a licensed electrician familiar with the rules and regulations of your jurisdiction before attempting anything with electricity. Most importantly, I will not be held liable for anything you read on the internet.