Why do so many guys not torque their main lugs to spec?

I keep finding 200 amp main breakers in new builds around Denver where the lugs are just cranked down by feel. The spec sheet for a Square D QO panel says 50 inch pounds, but I've seen guys use a regular socket and just go tight. That can cause hot spots and melt the bus bar over time. How do you make sure your crew actually uses a torque wrench on every panel?

3 comments

3 Comments

felix_henderson543d ago

My buddy's house in Aurora had a melted bus bar from that exact "cranked by feel" method.

danielb433d ago

Felix, that's a scary story and exactly why we got strict too. Evan_campbell's old foreman had the right idea with leaving the wrench out. We started a rule where the last guy to touch a lug had to initial it with a paint pen right on the panel label. If something came back loose, there was no question who did it. It made people pay attention real quick because their name was literally on the line.

evan_campbell4d ago

My old foreman in Colorado Springs had a strict rule, we had to leave the torque wrench on top of the panel until the inspection was done. He'd check for tool marks on the lugs and if the wrench was put away, you were redoing every connection on your own time. It was the only way to make the habit stick for some guys.