# tightening breaker lugs



## Southeast Power

forgotflying said:


> Just wondering how many of you tighten down breaker lugs with a torque wrench? :jester:


I do and we put a witness mark on them too...


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## miller_elex

In industrial work, yes.


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## 76nemo

jrannis said:


> I do and we put a witness mark on them too...


 
What do you use for paint John?


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## erics37

I just turn 'em till the plastic cracks.


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## guest

erics37 said:


> I just turn 'em till the plastic cracks.


LOL been there, done that.

On a similar vein, I tried to seat a stubborn 40DP Zinsco breaker by putting a screwdriver on one of the terminals and smacking the end of the handle. The result? A busted 40DP breaker, a huge arc flash as the screwdriver went across both bus bars, a stub of what was a really good screwdriver, and an unusable section of bus. Oops.


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## Big John

Honest answer, if the breaker is less than 100A, I'm probably just gonna snug it by hand. Anything higher than that I torque, and if it's switchgear, I'll torque and cross the bolts.

-John


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## jwjrw

After realizing I had been over torquing my connections for years I started torquing my connections. Especially on AL conductors.


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## McClary’s Electrical

jwjrw said:


> After realizing I had been over torquing my connections for years I started torquing my connections. Especially on AL conductors.


 
Me too, I try to impress by doing stuff others don't. There's a market of people who want to hire people like you and I. We just have to target the right market.


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## Wirenuting

forgotflying said:


> Just wondering how many of you tighten down breaker lugs with a torque wrench? :jester:
> .


I have been wanting to torque things down for years. But the boss will not buy the tools. Says they cost to much. 
I keep telling him we have a $14,000,000,000,000 deficit and a few dollars won't break the bank. 
But he believes it cheaper to do things wrong the first, second, third time. 
With our time and your money, we can do anything.


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## erics37

I was installing a lug kit in a panel with copper bussing once, and I had the torque wrench and everything out, following the instructions.... I was torquing it down to the recommended setting and the copper threads in the bus stripped well before I got to the proper point!

That pissed me off for sure


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## Jlarson

I can think of a few situations where using a torque screwdriver or wrench would cause a problem. 

For example, I work on lots of control panels where the factory wires where tinned with solder, if you add a wire to a relay socket or breaker term or whatever you got to crank on it to make a good connection, use a torque driver and you'd probably leave loose connections.

Just sayin'


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## McClary’s Electrical

Jlarson said:


> I can think of a few situations where using a torque screwdriver or wrench would cause a problem.
> 
> For example, I work on lots of control panels where the factory wires where tinned with solder, if you add a wire to a relay socket or breaker term or whatever you got to crank on it to make a good connection, use a torque driver and you'd probably leave loose connections.
> 
> Just sayin'


 

A tinned wire or untinned wire requires no adjustment for the lug torque. It's more about not deforming the lug and stretching the threads.


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## Jlarson

mcclary's electrical said:


> A tinned wire or untinned wire requires no adjustment for the lug torque. It's more about not deforming the lug and stretching the threads.


I've gone behind others that used torque drivers on control panels with existing tinned wire and I pulled out ever single new untinned wire by hand, not one was tight enough, didn't matter if it was a lug, pressure plate, whatever although I'm assuming the driver was set right by the operator :whistling2::laughing:


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## 76nemo

mcclary's electrical said:


> A tinned wire or untinned wire requires no adjustment for the lug torque. It's more about not deforming the lug and stretching the threads.


 
Sorry to ask or bug you, but can you possibly back that up on paper? That to me is word of mouth. I have never seen that on paper, and would be the first to disagree. Are you stating that because you've never seen it spec'd one way or the other, thus not specific?


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## McClary’s Electrical

76nemo said:


> Sorry to ask or bug you, but can you possibly back that up on paper? That to me is word of mouth. I have never seen that on paper, and would be the first to disagree. Are you stating that because you've never seen it spec'd one way or the other, thus not specific?


 


I'm stating the torque spec is there to keep you from damaging threads, and stretching the metal the lug is made out of. So, NO MATTER WHAT you put in it, copper, aluminum, tinned copper, or steel, it still does not give you the right, and especially does not require you to, over torque the lug due to what's UNDER the lug.


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## RedHeadElectric

I use a torquing screwdriver


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## TOOL_5150

I tend to only torque feeder and service connections in resi, I only torque branch circuits when I am required to.

~Matt


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## Mike_586

jwjrw said:


> After realizing I had been over torquing my connections for years I started torquing my connections. Especially on AL conductors.


Yeah and the way you did things is no different than how the vast majority of us go about or days. Hell it was in the trade for years before I ever saw someone torque something with the proper tool, most guys just crank things until 'feels tight'.

The absolute worst case I know of happened last spring in either March or April 2010. The ESA got a few calls from new home owners complaining that all their electronics were getting fried. The ESA showed up, started investigating and found the neutral lugs on the meter bases had burned up.

All the houses were done by the same contractor, so the inspector calls up the contractor, he blamed the manufacturer and said they had to be defective. It was either Siemens or Cutler Hammer, but whichever it was had an engineer on site with paperwork, checked out the meter bases and concluded the lugs were over torqued and produced paper work that proved it and gave the inspector a good idea just by how much the sparkies over torqued the lugs.

It resulted in a life safety order on the work, not just the few houses, but all the houses they did in that sub division. This is not a fix it at your earliest opportunity thing, its a drop everything and fix it now kinda thing. The company had to repair over 100 meter bases and got it done in around 5 or 6 hours.

Hearing that story and seeing the pictures is something that opened my eyes a little more.


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## LegacyofTroy

Urban legend? Or Guess I better get torque set.


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## mattsilkwood

Mike_586 said:


> Yeah and the way you did things is no different than how the vast majority of us go about or days. Hell it was in the trade for years before I ever saw someone torque something with the proper tool, most guys just crank things until 'feels tight'.
> 
> The absolute worst case I know of happened last spring in either March or April 2010. The ESA got a few calls from new home owners complaining that all their electronics were getting fried. The ESA showed up, started investigating and found the neutral lugs on the meter bases had burned up.
> 
> All the houses were done by the same contractor, so the inspector calls up the contractor, he blamed the manufacturer and said they had to be defective. It was either Siemens or Cutler Hammer, but whichever it was had an engineer on site with paperwork, checked out the meter bases and concluded the lugs were over torqued and produced paper work that proved it and gave the inspector a good idea just by how much the sparkies over torqued the lugs.
> 
> It resulted in a life safety order on the work, not just the few houses, but all the houses they did in that sub division. This is not a fix it at your earliest opportunity thing, its a drop everything and fix it now kinda thing. The company had to repair over 100 meter bases and got it done in around 5 or 6 hours.
> 
> Hearing that story and seeing the pictures is something that opened my eyes a little more.


 I call BS.
I can see the manufacturer citing improper torque, that part is totally believable, but I can't see being able to tighten a meterbase to the point that it's going to cause a problem without it breaking.


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## electricalperson

i always torque down breakers and feeders/service conductors. i dont torque breakers in a residential panel only commercial. i have a torque screwdriver and 3 torque wrenches with allen keys similar to kens. i bought mine from proto tools and made a 1/2 inch one with a socket and allen key. 

at my old company nobody believed in using torque wrenches to tighten down conductors. they tightened until they couldnt anymore. if you over tighten a conductor it damages it pretty bad. you dont want to crush the conductor so the metal flows you just want it to hold. i never broke a meter socket or stripped a lug when i use a torque wrench. one of the new journeymen used to break meter sockets all the time by putting all his muscle into it


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## electures

forgotflying said:


> Just wondering how many of you tighten down breaker lugs with a torque wrench? :jester:
> I do for anything commercial but for residential I don't.


http://www.electriciantalk.com/f2/torque-wrenches-torque-screwdrivers-4279/


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## Southeast Power

76nemo said:


> What do you use for paint John?


Sorry it took so long to get back to you.

I will locate the torque value on the label in the gear and if possible, underline it or highlight it, I torque the termination to that value and then, with just a sharpie, I mark the lug and the screw with a slash.
This is not anyone's specification by far but it does mitigate the risk of completely missing a termination. Also, if space permits, I will write the torque value on the lug.
It is very easy to get into the habit of using a torque wrench due to the fact that you usually need a ratchet and a hex head for the termination.

I had a job a couple of years ago where I had over 100 large terminations. I made a torque log and tossed it in with the permit documents. The inspector took one look at that and just about signed me off right there.

I really like to break out the torque wrench when I have a "helpful" maintenance man looking over my shoulder.


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## Southeast Power

mattsilkwood said:


> I call BS.
> I can see the manufacturer citing improper torque, that part is totally believable, but I can't see being able to tighten a meterbase to the point that it's going to cause a problem without it breaking.


I have had plenty of crappy loose connections right out of the box on almost any size gear. I try to check them before I install them. Im sure that is what happened to that residential meter base job Mike posted.


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## RedHeadElectric

I don't understand why some of you say you will torque breakers for commercial, but not residential? Isn't it just as important to follow the manufacturer's specs for a breaker in a house as it is in a shopping mall? I'd never be able to live with myself if a house I wired burned down and people or children lost their lives just because I didn't want to break my torquing screwdriver out.


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## LegacyofTroy

jrannis said:


> I have had plenty of crappy loose connections right out of the box on almost any size gear. I try to check them before I install them. Im sure that is what happened to that residential meter base job Mike posted.


I agree........some things you don't take for granted


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