Is anyone else picky about EMT connectors?

[Jpflex]

IMO steel set screw type is the best fitting for couplings and connectors. I believe that a few decades ago a study was done after an earthquake and it was found that the only type of fitting that survived was steel set screw. Die cast fittings broke and compression came apart.

I don't believe that and if it's true it's only based on lab results and not real world applications.
There's been too many times I've been in a tight corner where it's amazingly difficult to get channel locks on a compression fitting to get it sinched down. Plus there's no way that compression fitting ring that bites the EMT is not any thicker than my fingernail.

Perhaps the compression fittings were never tightened. The set screw type connector only has tight bonding from the diameter of a small screw. I can’t see how this is better

 

[electrofelon]

Perhaps the compression fittings were never tightened. The set screw type connector only has tight bonding from the diameter of a small screw. I can’t see how this is better

Of course there is more contact than just the setscrew. You've got at least half of the entire fitting pressed right up against the EMT.

 

[LarryFine]

Has anyone ever actually seen where a fault caused a poor conduit connection to blow up?

 

[ActionDave]

Perhaps the compression fittings were never tightened.

No. Compression fittings suck. They look like a good idea until you use enough of them.

The set screw type connector only has tight bonding from the diameter of a small screw.

Look at that little edge on the compression ring that isn't any thicker than a finger nail and tell me how that's better than a set screw that bites ten times as hard into the conduit. Plus it's not nearly as difficult to get a screwdriver into a tight corner to tighten a set screw. Not the same for compression where you need enough room to swing a couple pair of channel lock pliers. It's the worst on large sizes of EMT, 2" and better. I'll take a set screw everyday all day, every time.

I can’t see how this is better

And unless you approach the subject with an open mind combined with some years of experience you won't see.

I would put the spec to use compression only connectors on my top five stupidest requirements list.

 

[ActionDave]

Has anyone ever actually seen where a fault caused a poor conduit connection to blow up?

I've seen some burning around fittings but it was likely from neutral current flowing.

 

[Max Headroom]

Doesn't the inside of the fitting have a shoulder that protects the conductor from the EMT , if you tighten the screw to the point where the conduit is bent inside of the protective shoulder of the fitting then wouldn't that increase the risk of damage to the conductor. I know reaming is supposed to insure the conduit doesn't damage the insulation but it seems like there is still a risk of that when tightening the set screw to the point of bending the conduit.

 

[LarryFine]

If the EMT is fully seated in the fitting, the screw(s) should make a dimple(s), not a crease.

 

[Jpflex]

No. Compression fittings suck. They look like a good idea until you use enough of them.

Look at that little edge on the compression ring that isn't any thicker than a finger nail and tell me how that's better than a set screw that bites ten times as hard into the conduit. Plus it's not nearly as difficult to get a screwdriver into a tight corner to tighten a set screw. Not the same for compression where you need enough room to swing a couple pair of channel lock pliers. It's the worst on large sizes of EMT, 2" and better. I'll take a set screw everyday all day, every time.

And unless you approach the subject with an open mind combined with some years of experience you won't see.

I would put the spec to use compression only connectors on my top five stupidest requirements list.

I’m not saying I’ve worked the industrial side as an electrician longer than you but I do have several years experience in both residential and industrial.

My thought is that a compression ring overall is much larger than the finger nail width you describe because the compression rin’s total cross sectional area encircles the entire EMT circumference to cover a much larger surface area of EMT rather than one pin size set screw bonding at only one point location. perhaps the problem with some compression connectors is not the design concept but manufactures going cheap on quality build and or electricians not applying enough torque or tightening couplings properly

 

[Max Headroom]

If the EMT is fully seated in the fitting, the screw(s) should make a dimple(s), not a crease.

That would be ideal and resduce the chances the conduit would pull apart! I will check that out next time I work with EMT/set screw fittings, thanks for the feedback, I hope you're right.

 

[ActionDave]

I’m not saying I’ve worked the industrial side as an electrician longer than you but I do have several years experience in both residential and industrial.

My thought is that a compression ring overall is much larger than the finger nail width you describe because the compression rin’s total cross sectional area encircles the entire EMT circumference to cover a much larger surface area of EMT rather than one pin size set screw bonding at only one point location. perhaps the problem with some compression connectors is not the design concept but manufactures going cheap on quality build and or electricians not applying enough torque or tightening couplings properly

It's the design itself that is flawed not the quality of the manufacturing. The bite on those compression rings is not that big, just because it goes all the way around the pipe doesn't change that. When you tighten the set screw you have even more surface area in contact between the conduit and the fitting than you do with a compression if that's what matters to you.

As far as electricians not applying enough torque, that's part of the problem with using them. There are many times I've been in a spot where it's near impossible to get a set of channel locks in and swing them enough to get any decent twist on the connector.

 

[Jpflex]

. There are many times I've been in a spot where it's near impossible to get a set of channel locks in and swing them enough to get any decent twist on the connector.

yes I agree and I noticed that compression type couplings can also be hard to tighten to connect two EMT runs where at least a 1/2 “ offset are not made at the EMT ends to allow the coupling collar wider than the EMT to rotate within the EMT runs secured flat against a wall.

I do actually make these offsets so I’m not one who has this problem however. Most other people are too lazy to ensure aesthetic detailed work

 

[gadfly56]

If the EMT is fully seated in the fitting, the screw(s) should make a dimple(s), not a crease.

Yes, that's always been my experience. I've never punched through the wall of the EMT with a set screw, and the dimple is smooth enough to never catch the cable you're pulling.

 

[__dan]

Steel only, almost never die cast although I have used them.

Saw recently the cheaply made steel ones. You had to back the screw out to get it over the pipe then the screw would fall out. If you made it that far it would strip going back in with a small impact tool. Screw would just spin in the fitting. Saw that last summer.

The square drives never seemed to fit the bit either. Swapping bits and bit sizes did not help with that. Saw pallets of them. The bad ones had a regular brand name, came from a supply house, but were clearly stamped INDIA.

 

[LarryFine]

The bad ones had a regular brand name, came from a supply house, but were clearly stamped INDIA.

Holy cow!

 

[readydave8]

aesthetic

Offsets at every coupling look good?

 

[LarryFine]

Offsets at every coupling look good?

They can also trigger a picky inspector to require pull points, as they technically are bends.

 

[Jpflex]

They can also trigger a picky inspector to require pull points, as they technically are bends.

Max offset is 360 degrees to code but most limit to 270 degrees

Keeping the emt flat with offsets is better than putting a hole / scratches into drywall when tightening couplings or unsightly work. Your aesthetics have a lot to do with your reputation and getting calls for more work

 

[Jpflex]

Offsets at every coupling look good?

Yes having EMT flush by using offsets does look good

 

[LarryFine]

Keeping the emt flat with offsets is better than putting a hole / scratches into drywall when tightening couplings or unsightly work. Your aesthetics have a lot to do with your reputation and getting calls for more work

Ohhh, that's what you meant. Why not tighten the couplings before tightening the mounting straps?

If it's that important, why not use shallow strut, or Minerallacs, or these:

 

[readydave8]

most limit to 270 degrees

most inspectors? or most electricians?