ECN Forum Forums General Topics of the Trade General Discussion Area Wire Torque

This question is really aimed at Don (Rescpt19) due to past posts on the subject but anyone with info please chime in!
I am starting a new job that had this requirement in the specifications.
Within 15 days prior to store turn over, re-torque all bolted wire connections in panels and switchboards, in compliance with applicable NEC requirements. Record date, connection location, and torque applied.
We’ll, the NEC doesn’t have any requirements to “re-torque” connections and according to Don it is a very bad practice. What I am wondering is if there is any published data on the consequences of re-torqueing wire connections and the effects it can cause. If I refuse to do this I will need some solid back up. Thanks.

I'm also interested in any ammo to help persuade...

It is common practice for the AHJ's around here to insist upon retorquing when an anti-oxidant has not been used (to apply said "noalox" or "penetrox"). I got a strange look when I asked if he made them cut and re-strip the wire to torque on "virgin" conductor... (sigh)

Lots of DYI work here and the AHJ is usually just happy to see line and load in the right places...

Virgil,
"DYI" referring to "Do Yourself In"?

Nick,
I have been told it is a bad practice, but cannot find any published documents to back up what I think that I was told a number of years ago. Maybe I'm just wrong on this point.
Don(resqcapt19)

Hee hee... Oooops Typo...

Nick
Ul Standard 486B, Table 1.3 through 1.6. These torque values are used when testing wire connectors, unless the manufacturer assigns another value appropriate for the design. These values are for guidance only if no tightening information is not available on the specific wire connector.
In your case, I think the requirment is written into the specifications so the values will be checked. You don't want to have a loose wire in a connector. Just set your torque wrench to the proper value, then check each one to insure they are all tight. If I were doing the project, I would only hand tighten each connection the first time through, then torque to the proper value on the second time around, noting the values for each one. Your obligation would then be properly fulfilled without overtorque on any connector.
We have this same statement in some of our specs, and I have never given it much thought until I read the thread on this BB. I will re-word my specs to account for this from now on.
Just a thought from the designer.

"Do Yourself In" -- I like it!

As opposed to DIY which really means "Destroy It Yourself."

Thanks guys, for the reply's.

I have seen on meter bases especially, a torque spec for different size wire etc. Does anyone really use a torque-wrench ?

Yep.

Inspectors up here expect to see one out if they come on site while the meter socket connections are being made.