Foot pounds of Torque for breakers and lugs.

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zog said:
I am shocked at the apparant lack of electricians that torque thier connections, again, another reason for 3rd party acceptance testing, we are required to check all connections for proper torque, and have calibrated wrenches.
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What you work on is so much different then I bet 95% of the electricians in this country work on it is almost like you are in a different trade altogether.

There is a torque value given for all terminations. If you think most electricians should break out a torque screw driver for installing every 14 AWG to every single switch and receptacle then I think you are in for a disappointment.

I know I don't torque branch circuits at either the breaker or device end.
 
zog said:
I am shocked at the apparant lack of electricians that torque thier connections, again, another reason for 3rd party acceptance testing, we are required to check all connections for proper torque, and have calibrated wrenches.

We even have to know these specs for our certification exams, see attached table 100.12 from NETA ATS
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I'm not a NECnut but from what I've seen here, if it isn't in NEC, it don't get done! Are torque specs listed in NEC, what to follow, etc.?

Nice chart but why no thread pitch listings? A 1/4"-28 thread can be torqued higher than a 1/4"-20.

I have a ITE 30A double-pole breaker using 1/4"-28 screws tagged for 25 in/lbs. What does your chart state? Charts I found showed 72 in/lbs for a 1/4-20 and 90 in/lbs for a 1/4"-28, so manufactures specs don't coincide with torque specs for fastners in general.
 
wptski said:
I have a ITE 30A double-pole breaker using 1/4"-28 screws tagged for 25 in/lbs. What does your chart state? Charts I found showed 72 in/lbs for a 1/4-20 and 90 in/lbs for a 1/4"-28, so manufactures specs don't coincide with torque specs for fastners in general.
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Torque values for terminating busbars and conductors are different than the torque values for mechanical connections.
 
most breakers have the torque specs on them, at least the ones that we have, if not ask your supplier what they are if the company is a good supply house they should have the specs.
 
when we do our pm's we use a torquing screw driver, and when we do substations, we use the torque wrench, guide lines are set by the manufacture.
 
electricalperson said:
i have a set of craftsmen 3/8 socket drive allen keys but they dont really grab that well. what brand is everyone else using to torque allen key lugs?
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What you mean by "don't grab that well"? Not long enough? Proto makes them with a longer allen wrench.
 
wptski said:
Nope, torque is torque, no matter where or what it's used on.
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No.

Do not use the torque values for say a grade 3 -1/4" x 28 mechanical connection in a piece of machinery for say the 1/4" x 28 screw in a breaker. The result will be a crushed wire and likely broken parts.
 
iwire said:
No.

Do not use the torque values for say a grade 3 -1/4" x 28 mechanical connection in a piece of machinery for say the 1/4" x 28 screw in a breaker. The result will be a crushed wire and likely broken parts.
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I stated above that the beaker was marked for 25 in/lbs but the max torque for a 1/4"-28 screw 2-3 higher. You'd use the breaker manufacturer's specs not Acme Bolt Company, etc. or you would mash the wire.
 
electricalperson said:
they strip sometimes. i havnt used them in a while because of that
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Well they are either worn out or your using standard with metric hardware.

If they are worn out just bring them back to Sears and get them replaced for free.

You should have both metric and standard Allen sockets.

It also helps to have some long ones as well for torquing breakers with recessed fasteners.
 
electricalperson said:
they strip sometimes. i havnt used them in a while because of that
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Like mention, sure your not using them on metric screws?

I've had a Craftman set for over thirty years, maybe not the original allen bits in them now because as they wear, your sharpen them up on a grinding wheel and when they get too short, you replace the allen bit.
 
ironman3452 said:
when we do our pm's we use a torquing screw driver, and when we do substations, we use the torque wrench, guide lines are set by the manufacture.
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What kind of wire, terminations, etc? What kind of torque settings are you using with a torque screwdriver?
 
iwire said:
Well they are either worn out or your using standard with metric hardware.

If they are worn out just bring them back to Sears and get them replaced for free.

You should have both metric and standard Allen sockets.

It also helps to have some long ones as well for torquing breakers with recessed fasteners.
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there pretty much brand new i only used them a few times. plus they are standard size. can you link me some high quality ones that you would use?
 
electricalperson said:
there pretty much brand new i only used them a few times. plus they are standard size. can you link me some high quality ones that you would use?
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I have both Craftsman and Snap on, really makes no difference.

Either your not sticking them in the lug far enough before turning, or the hardware is metric or already damaged.

Lastly maybe your just trying to tighten them to much. Aluminum set screws are pretty soft compared to tool steel.
 
Square D has a circuit breaker with shallow Allen sets, if you do not press hard on the wrench as you torque the connection the Allen set strips out.
 
iwire said:
Lastly maybe your just trying to tighten them to much. Aluminum set screws are pretty soft compared to tool steel.
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Setscrews can be made from aluminum, stainless steel, brass and carbon steel which is case hardened but never "tool steel" which is what cutting tools are made of.
 
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