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HeyBub

wrote:
Hi. I've a newbie question.
My circuit breaker panel has 240volt service entering it. I removed
the cover to investigate how the breakers are installed and tested
some of the breaker leads with a voltmeter. The breakers are
arranged in 2 columns, with 6 breakers in each column. I see two
black cables, one to each column, and one white cable to the neutral
bus.

While holding the probe to the lowest circuit breaker in the first
column ("R#1, C#1") , I found that the next row up in the same column
("R#2,C#1) had no difference in potential. But both were 120V above
neutral (which makes sense to me). However, the difference between
R#1,C#1 and R#3,C#1 was 240 volts. Same for R#1,C#1 and R#4,C#1.
R#5 & R#6 go back to no difference in potential over R#1.

Is there some type of standard crisscross pattern of feeders behind
the circuit breakers? I remember reading about this somewhere...
maybe to reduce the chance of overloading one feeder over the other??

I'm sure any electrician or someone familiar with an empty breaker box
can answer this. Please help.

Yes. The bus for each leg serpentines to alternate connections. Next time
you're at HD, look at an empty box and it'll be crystal clear.