I heard a story at work today that a guy that worked at our shop a while back before i was hired. Ran 2 wires of a 3phase system in one section of conduit and the third wire in another section of conduit about a foot or less apart and when he threw the switch the system shook the conduit apart and it fell apart before they got it shut down or it tripped out. that was the last time he ran electric they said. is this due to the magnetic effects and the phases or is this bull. i have 8 yrs of experience but i have never heard of this. but i always run my wire to code also.
