distro 20 amp edison circuit question


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distro 300 amps main breaker
edison (36) @20 amps
L6-30 (3) @ 30amps
L21-30 (3) @ 30amps

my questions are :

(1) is each individual circuit at 20 amps?

for example pic 1 : circuit #1 has top and bottom . are both top and bottom together at 20 amps?
or example pic 2: are both top and bottom individually at 20 amps? or is top and bottom both divided equally ( 10 amps each)?

(2)Total amperage is 300 amps?

[how to make these calculations?
L6-30 (30x3 =90 amps)
L21-30 (30x3= 90 amps)
Edison (36x20 ........???) ]


  • distro 1.png
    distro 1.png
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  • distro 2.png
    distro 2.png
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(2)Total amperage is 300 amps?

[how to make these calculations?
L6-30 (30x3 =90 amps)
L21-30 (30x3= 90 amps)
Edison (36x20 ........???) ]
A 300 Amp main breaker on a distro would be a new one for me - 150, 200, 400 are more common.

Whatever the main breaker is rated is rated per phase. If the load is not balanced it is possible to trip the main breaker with one leg overloaded.

The Edison outlets in the photo are color coded, the top two banks are going to pull from the black phase, the middle two the red phase and the bottom two the blue phase. L6-30 connectors will pull from two phases. The L21-30 will pull from all three phases - depending on what the load is. Richard Cadena has some books that will help you learn more about power distribution https://www.rcad.me/books
.....Count the breakers on each panel. 6 breakers, 6 circuits, 12 outlets, divide. Now, there is zero standard when it comes to distros. While not typical, you could easily order this rack with each Edison on its own circuit. And of course when using a distro its only as strong as its most loaded leg.
My estimation is that those are individual pieces, and it's not clear how they're terminated to the incoming camlok, and whether there's a main breaker to protect the cable. So your question 2 may not have an answer yet.

Pic of the back?
Other than being a more robust build and higher plug retention and 3 colors, they're functionally the same as the duplex outlets in your home or office. Each duplex is protected by 1 20 amp circuit breaker, presuming it's wired the way the layout implies. The 3 colors are 1 for each Line (phase).

Service is rated on the ampacity of an individual line, not the sum of the lines. A 200 amp, 120V/208V 3 phase wye service would be protected by a 3 pole 200 amp breaker, or 3 individual 200 amp fuses (one per line).

Jay's inquiry as to how it's all wired up inside is certainly worth pursuing. A pic of the other side of this rack would be helpful.
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Knowing that particular manufacturer, if each outlet was a separate circuit it would be labeled that way. The fact that only each duplex is labeled indicates that it is not split but on a single circuit.
Usually, but it depends on how the manufacturer or customer chooses to have it wired. Usually with 120v circuits 1 and 2 would be phase A, circuits 3 and 4 would be phase B, and circuits 5 and 6 would be phase C. And with 208v you would have 2 that were A and B, 2 that are A and C, and 2 that are B and C. That helps to keep the load balanced on all 3 phases no matter how many soco cables your using on any given day.

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