ECN Forum Forums General Topics of the Trade General Discussion Area What Should A Commercial Electrician Know?

My pipe bending skills are minimal. I've taken the pipe bending course at Vo Tech but like most resi elec's we don't get to do much bending. I know all the multipliers and can bend 1/2" and 3/4" emt pretty good but the bigger benders I've never used on job sites.

I'm not totally unfamiliar with 3 phase.

Black, red, blue is normally a 120/208 Wye system with a grounded conductor
Black, red, blue can also be an open delta system where the 'wild leg' is 208 volts to ground should be phase 'B' indentified in orange
Brown, orange, yellow is a 277/480 volt wye system with a grounded conductor
277 volt is a single phase voltage
480 volt is either 2-pole, or 3-pole
3-phase motors have only run windings, no start windings
If a 3-phase motor is operating backwards, reverse two of the leads

PLC's I know nothing about.

Motor starters and controls I somewhat know