On 6/18/2011 10:20 PM, William Sommerwerck wrote:
I should have explained that I went to remove the element without
opening the breaker -- on the assumption that no engineer in his
right mind would leave one side of the heating element powered.

Are you stupid? NOTHING gets worked on while connected to power.

"Foolish" might be more apt than "stupid". And people commonly work on
powered TVs and other electronic equipment -- with proper precautions, of
course.

We still need an answer to the original question... Why?

Um, stupid is the correct term William.

"Bench testing live equipment" is NOT the same as working on
an oven connected to a 240 circuit.

As to why it only opens one side of the circuit, that's simple,
it only requires one switch to open a series circuit. It takes
two to remove power. Hence the coupled dual pole breakers on
the source (breaker) panel.

Jeff


--
"Everything from Crackers to Coffins"