110.14D

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We're on NEC 2014, so I couldn't find 110.14D

But we've be required in certain jurisdictions (Palo Alto is one) to provide proof of torquing for many years.

We torque all connections in the panel prior to inspection, then the inspector will ask us to torque a few random connections in the panel (2 or 3 breakers, 2 or 3 grounds, 2 or 3 neutrals) to show it's been done properly.
 
electricguy61 said:
, then the inspector will ask us to torque a few random connections in the panel (2 or 3 breakers, 2 or 3 grounds, 2 or 3 neutrals) to show it's been done properly.
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A proper torque is to tighten until the correct torque is reached and to not tighten again, inspectors are asking you to add more torque to something that has already been done properly.

If they are not there to witness original tightening the only proper way to verify is to loosen and then tighten again.
 
kwired said:
A proper torque is to tighten until the correct torque is reached and to not tighten again, inspectors are asking you to add more torque to something that has already been done properly.

If they are not there to witness original tightening the only proper way to verify is to loosen and then tighten again.
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Yay once torqued it is done.
How can this requirement be enforced?
Do some states require the inspector be present for service equipment torquing?
 
ActionDave said:
I think if this catches on a lot of guys are going to be surprised at how light the torque specs are compared to how tight they used to making connections.
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i totally agree. I recently did a comparison and realized how much may not be needed to achieve proper torgue
 
Hex lugs will tend to get overtightened without a torque wrench.

Slot head screws may often never be tightened to their specification without a torque wrench. A breaker with slot head screws and a tightening spec of 20 in-lb about takes your wrist out if you go through a full 42 circuit panel with a "torque screwdriver" and tighten all the connections to spec. I know I don't normally turn them that tight with a basic screwdriver.
 
Yeah, I mean if the torque screwdriver shaft has 1" radius, you figure you gotta put 20 pounds on it to make that click. That's a world of difference from doing 20 in/lbs on the end of a 16" ratchet.
 
ActionDave said:
I think if this catches on a lot of guys are going to be surprised at how light the torque specs are compared to how tight they used to making connections.
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K8MHZ said:
You bet they will!

Too tight is just as bad as too loose.
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Well, I always torque until the screw strips and then back off a quarter turn. :p

I have seen connections that have been there for half a century and nary a problem and those guys would never have though of useing a torque screw driver. German torque: gut-un-tite.
 
growler said:
Well, I always torque until the screw strips and then back off a quarter turn. :p
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:thumbsup:

We must remember the NEC is a minimum set of specs, so torque values should be minimums, too, right? :lol:


I have seen connections that have been there for half a century and nary a problem and those guys would never have though of useing a torque screw driver.
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And I have seen butt loads that have come loose that would not have if a torque tool was used.
 
kwired said:
Slot head screws may often never be tightened to their specification without a torque wrench.
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I take it you have never seen a big Klein rubber gripped flat screw driver in the hands of a burly 'lectrician. Those are REAL screw drivers and I can probably break the head off a #10 screw with one. Not everyone uses the proper sized screwdriver, since bigger is better and all.
 
K8MHZ said:
And I have seen butt loads that have come loose that would not have if a torque tool was used.
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If every connection was torqued correctly by someone that really cared useing a torque wrench/driver that had recently been calibrated you could have something.

What are the odds on that happening:?.

The reason for poor connections is no one gave a darn in the first place.
 
K8MHZ said:
I take it you have never seen a big Klein rubber gripped flat screw driver in the hands of a burly 'lectrician.
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I actually broke one of those square shanked industrial strength screw drivers one time, with one hand. I was on the top step of a 12 ft. ladder (OSHA was not around) leaning out to tighten a screw and the end broke of and landed on an even bigger HVAC mechanic's hard hat and he was wearing it. I thought there was going to be a bit of trouble. He didn't look to be a happy camper. I explained that this particular screw driver was brand new and that I had ordered it from the supply house just that morning and they don't come that are supposed to be of a better quality. After examining said screw driver he said "I'll be dam&&". And they sould give me a new one. But the supply house would not give a replacement because they said they had never herd of one breaking during normal useage.

By the way the metal didn't break the handle did. Snapped right off. I hadn't even gotten around to beating on it or abuseing it in any way.
 
growler said:
I actually broke one of those square shanked industrial strength screw drivers one time, with one hand. I was on the top step of a 12 ft. ladder (OSHA was not around) leaning out to tighten a screw and the end broke of and landed on an even bigger HVAC mechanic's hard hat and he was wearing it. I thought there was going to be a bit of trouble. He didn't look to be a happy camper. I explained that this particular screw driver was brand new and that I had ordered it from the supply house just that morning and they don't come that are supposed to be of a better quality. After examining said screw driver he said "I'll be dam&&". And they sould give me a new one. But the supply house would not give a replacement because they said they had never herd of one breaking during normal useage.

By the way the metal didn't break the handle did. Snapped right off. I hadn't even gotten around to beating on it or abuseing it in any way.
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That was a manufacturing defect, I am sure. I have two or three of them and I beat the crap out of them and have never broke one.
 
growler said:
If every connection was torqued correctly by someone that really cared useing a torque wrench/driver that had recently been calibrated you could have something.

What are the odds on that happening:?.

The reason for poor connections is no one gave a darn in the first place.
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You have never seen a connection fail on a breaker that was obviously over tightened? I have. Solid conductor flattened, and worked loose from years of thermal cycling.
 
K8MHZ said:
You have never seen a connection fail on a breaker that was obviously over tightened? I have. Solid conductor flattened, and worked loose from years of thermal cycling.
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Usually on larger conductor terminals though. If the terminals use slot screwdriver, the one's I have paid attention to recommended torque are usually 20-25 in-lb. When I have used a torque screwdriver to properly tighten to that level it made me realize I never turn that tight with a regular screwdriver, and my wrists would have been destroyed years ago if I had tightened all the terminals I did to proper tightness with a regular screwdriver. I was still young and dumb when I noticed how tight 20-25 in-lb is.

Is there any accurate torquing devices out there that can be used with driver-drills?
 
kwired said:
Is there any accurate torquing devices out there that can be used with driver-drills?
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I have seen equipment installers (Sleep Number beds) use a single size single purpose hex socket adapter for their drill-driver that has a fixed release torque value. No idea how well it holds its calibration though.
The company requires them to use it for tightening specific screws/bolts.
They had to borrow my drill driver though, since theirs was broken! :)
 
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