Wire Clamps Required with Conduit?

[nwav8tor]

I know clamps are required where romex enters a panel or box, but what if you use individual THHN wires in EMT? The EMT gets connected to the panel enclosure or the box, but I don't know if there is a type of clamp you use in such a situation or if it's OK to just leave the wires "loose" since they're enclosed in the EMT. (Can you tell I'm new at this?)

Thanks,
Paul

 

[sberry]

They are in conduit, they are fine.

 

[pattenp]

Yep, no clamps are needed where the wire exits the conduit to inside the panel.

 

[mrjaw14]

The NEC has changed their rules for connections to a box where a threaded connector is used.

Basically no you don't need a cable clamp with EMT or rigid going to a junction box or panel, but you can't have exposed threads... if the wire is 4 gauge or larger. they say that a strain on the wire can pierce the insulation on the threads and cause a hazard. Inspectors will want to see the little plastic bushings covering the threads if the wire is over 4 awg. They're so cheap that even though I technically didn't need them on anything except my feeder entrance I used them everywhere

Edit: I know you're probably not using 4 gauge wire, just throwing this out as an FYI

 

[MrMark]

Really, I thought that was an old rule. I've always tried to do that. It's just common sense to prevent chafing.

 

[foolishpride]

I know clamps are required where romex enters a panel or box, but what if you use individual THHN wires in EMT? The EMT gets connected to the panel enclosure or the box, but I don't know if there is a type of clamp you use in such a situation or if it's OK to just leave the wires "loose" since they're enclosed in the EMT. (Can you tell I'm new at this?)

Thanks,
Paul

I'm not real clear what you mean by "clamp". Are you talking about an EMT connector?

Or are you talking about a strap to anchor the conduit?

 

[nwav8tor]

The NEC has changed their rules for connections to a box where a threaded connector is used.

Basically no you don't need a cable clamp with EMT or rigid going to a junction box or panel, but you can't have exposed threads... if the wire is 4 gauge or larger. they say that a strain on the wire can pierce the insulation on the threads and cause a hazard. Inspectors will want to see the little plastic bushings covering the threads if the wire is over 4 awg. They're so cheap that even though I technically didn't need them on anything except my feeder entrance I used them everywhere

Edit: I know you're probably not using 4 gauge wire, just throwing this out as an FYI

I'm now thinking of using three #2 (or #4 with a residnential exemption) wires for the 100A feeder from the main service panel to the new sub-panel. plus a #8 ground. I'm hoping to put it in 1-1/4" flexible metal conduit for the short run down from the main, through a stud and up into the sub. That should mean a threaded connection at each end. I don't know what the bushings you're talking about look like or how/where they are used.

Thanks,
paul

 

[pattenp]

Conduit end bushing, this one is for PVC.

This one is for metal....

 

[pattenp]

Are the 3 #2's that you are planning to use, copper? The reason I ask is #2 aluminum is not good for 100A.

 

[fnsane]

You guys need to hire a LICENSED electrical contractor.

 

[pattenp]

Just who are the "You guys" that you are directing that comment to?

You guys need to hire a LICENSED electrical contractor.

 

[jeff000]

OP, I think you might be in over your head.

Conduit end bushing, this one is for PVC.

This one is for metal....

No, you can use the PVC on EMT/rigid connectors. No need for a bushing on PVC connectors.

 

[Norcal]

OP, I think you might be in over your head.




No, you can use the PVC on EMT/rigid connectors. No need for a bushing on PVC connectors.

If the conductors are #4 and larger, there are no exceptions for PVC.....

 

[jbberns]

If the conductors are #4 and larger, there are no exceptions for PVC.....

+1 agreed

 

[nwav8tor]

Conduit end bushings - now I get the picture.

All wiring will be CU...

Not in over my head, but still am planning to have my worked checked by an electrician before I get my final inspection...

Thanks,
Paul