I am 2nd year 1st semester student at Independent Electrical Contractors of Rocky Mountain. This question is from our final Review:
This is a fairly straightforward Ohm's law question. Each ungrounded conductor is carrying how many amps? 8200 kW / 240 V = 34.16 A; we round up to 34.2 A and we're good.
Anyway, I remember a question from a past review that is similar and made me think about this question a little bit:
This question is similar: how many amps in each conduit on A phase are being carried to the subpanel? A phase is carrying 210 A; we divide by two, and come up with 105 A. Looking at the questions individually they make sense, but when they are side by side I get confused.
Looking at the first question we know that AC current is flowing back or forth on the conductors headed to breakers 6 and 8. The amps is 34.2 A.
On the second question, we have four conductors headed to a 2 pole breaker. I don't know a lot about panels and breakers, but I think each breaker corresponds to a phase in this case. Will call the breaker the red wire goes to A phase, so I guess if that subpanel is pulling 210 A, 105 A will flow through each conductor.
I think I'm overthinking this. I also think I might be missing something because the connections are in parallel on the bottom and in series on the top.