Retorquing

A

AC\DC

Senior Member
Location
Florence,Oregon,Lane
Occupation
EC
I found a UL standard that says you’re not supposed to retoque a termination of properly torqued. They says if completely necessary, you can set a torque screwdriver at 90% and re-torque but by that phrasing it sounds like that’s the last case. Scenario

Am I correct cause I just got an argument with a mechanical engineer that says they retourqu the time and I told him you’re not supposed to. I sent him that information and he says I’m full of caca
 
Electrical connections for terminating 'wire' are not mechanical connections.
Follow the electrical industry recommendations, such as the ones from UL.
 
AC\DC said:
I didn’t say they were mechanical connections. I said I was talking with a mechanical engineer.
Click to expand...
You and the mechanical engineer may be talking past each other. I'm sure he's thinking about nuts and bolts for fastening structures and not at all considering that the electrical subset of fasteners are treated differently.
 
gadfly56 said:
You and the mechanical engineer may be talking past each other. I'm sure he's thinking about nuts and bolts for fastening structures and not at all considering that the electrical subset of fasteners are treated differently.
Click to expand...
Nope, he called me in regards to a shifty contractor that another form I was bitching about he wants me to go and retorque all electric connections because that’s what that shady contractor says he’s gonna do and I told him you don’t retorque then, you on land them cut them and start fresh. There is an allowance at 90%, but that doesn’t guarantee nothing.

He’s an engineer so he got all on his soapbox preaching that he does it all the time no offense the engineer my dad was a civil engineer so I know how they think
 
I've seen equipment labels that require you to re-torque connections. There are many places that include re-torqueing as part of routine maintenance.
 
infinity said:
I've seen equipment labels that require you to re-torque connections. There are many places that include re-torqueing as part of routine maintenance.
Click to expand...
Yeah, retorquing but does that mean you cut it off and start fresh..,,,
I submitted an Nema publication stating that

Maybe manufacturer instructions supersede the Nema standard that I posted but I don’t think my fithty year-old equipment has that allowance in it

Maybe I’m wrong wouldn’t be the first
 
AC\DC said:
Nope, he called me in regards to a shifty contractor that another form I was bitching about he wants me to go and retorque all electric connections because that’s what that shady contractor says he’s gonna do and I told him you don’t retorque then, you on land them cut them and start fresh. There is an allowance at 90%, but that doesn’t guarantee nothing.

He’s an engineer so he got all on his soapbox preaching that he does it all the time no offense the engineer my dad was a civil engineer so I know how they think
Click to expand...
OK then, sounds like the engineer missed a golden opportunity to learn something. I try very hard not to be that guy.
 
gadfly56 said:
OK then, sounds like the engineer missed a golden opportunity to learn something. I try very hard not to be that guy.
Click to expand...
Well, I have a thing with you engineers because my dad always throws that he’s an engineer. He knows everything so I’m a little jaded by that, but am I understanding this wrong or understanding it wrong?

If I’m wrong, I just wanna know I’m wrong
 
AC\DC said:
Yeah, retorquing but does that mean you cut it off and start fresh..,,
Click to expand...
I don't think anyone would construe this to mean that the equipment needs the conductors to be removed, trimmed, and reconnected.

What is so wrong with checking the connections to ensure that they're tightened correctly?

Lug Retighten.jpg
 
according to the nema paper I uploaded- yes using a torque equipment is only for the last resort. And you have to set to 90%
Ira or visual is the recommended way.

Guess it does not state cutting wires—- but it’s seems better then doing the 90% torque. If it was over tightened on install the 90% won’t show you crap
 
I had an EC that always retorqued, without first loosening, connections. Once during a Christmas shutdown they managed to break the studs on a plant's 12470V incoming lugs. That shutdown last days longer than the customer was expecting.
 
After doing some more research, it seems like it’s one of those huge gray areas that the code and it seems like this industry loves. Because if you retort it’s not the same torque value as a brand new install so by taking it off and cutting it it’s a brand new install. so it should be at the proper torque value, but conductors that they landed and then retorqued to the proper torque, but that wires already been compressed so it’s gonna torque at a different value than a new
installation so there’s no right or wrong

Doing speak to chat and for some reason, retoruqu is not coming out right
 
AC\DC said:
As I see that sticker, so what’s the proper way then?
Just do it at 90% and say oh well

Guess I am wrong you can just retorque
Click to expand...
I think that the NEMA bulleting can be taken as a general guideline. However, if a manufacturer puts periodic retorquing in there installation guide, I would believe you'd be bound by the instructions. So I guess the final answer is, "it depends".
 
AC\DC said:
new installation so there’s no right or wrong
Click to expand...
I think that this is something that's open to interpretation so the answer depends on who you ask. Years ago (not sure if they do it anymore) we had a contract with a company that did maintenance for American Express in their data center in NYC. Given that nature of their business data reliability is critical so once a year at midnight on a weekend they would shutdown all of their panels and PDU's and we would go in open them up and check every single connection, even 20 amp branch circuit breakers. This was before anyone had a torque screwdriver so the breakers would be checked by hand tightening. Large feeder lugs were checked with a torque wrench. They always clicked before the terminal moved so they were still tight from the year before. I'm guessing that they no longer do this type of maintenance when you now can just IR scan the equipment.
 
gadfly56 said:
I think that the NEMA bulleting can be taken as a general guideline. However, if a manufacturer puts periodic retorquing in there installation guide, I would believe you'd be bound by the instructions. So I guess the final answer is, "it depends".
Click to expand...
So I know manufacturers can’t supersede the NEC
But nema just a guideline or just the paper I submitted ? I’ll dive more into it.

Seems like it’s a marriage both are right and wrong at the same time lol
 
infinity said:
I'm guessing that they no longer do this type of maintenance when you now can just IR scan the equipment.
Click to expand...
A properly torqued connection should not need to be retorqued.
IR scanning is a better tool to locate suspect connections.
 
You must log in or register to reply here.
Top