Conduit Type in Electrical Rooms

[Carultch]

It shares the same crock of baloney as specing insulated throat connectors. There's no gain in safety. The double proof is that the stupid plastic falls out of the end of all but about three connectors on the whole building so every place that has them installed ends up being no different than a building with non insulated throat.

I thought the point of the insulated throat, is to have the purpose of the plastic bushing integrated in the connector, so you don't need to separately supply it.

 

[Another C10]

A contractor is asking clarification of a specification requirement. I don't like how the spec was worded, but let's ignore that for the moment. What type(s) of conduit do you use between panels inside the electrical room? Are there any types that you would not use? My view is that such rooms are not places in which a conduit could be subjected to severe physical damage. Am I wrong about that?

Emt is the best way to go, looks clean, is sturdy and as far as physical damage .. remember the damage could be from other workers or trades working within the area whether its a panel room, warehouse or above a T bar ceiling. Besides emt is a great grounding path.

There is no good reason. some will have reasons, but there is about as many pros as there is cons either way on this.

My take on this comment is, I prefer compression just because its a better bond and stronger connection, moisture, dust and fumes wont likely penetrate either , although set screw connections may lay flatter on a surface the screws tend to snap or strip, besides the conduit connection has less of a surface area bond allowing for arcing to potentially occur if subjected, I always pull a ground anyway.


Just a shared note. Sincerely, Mark

 

[infinity]

In my opinion and in my experience compression fittings are inferior to set screw. Set screw fittings are easier to confirm that the pipe is inserted to the proper depth, easier to tighten, easier to identify as not being tightened, and provide a better bite. I've done a ton of commercial remodels and I can promise you that compression fittings are way easier to demo out and pull apart than set screw.

The reason for specing compression fittings is so someone can say, "I'm better than you because I spec these." It shares the same crock of baloney as specing insulated throat connectors. There's no gain in safety. The double proof is that the stupid plastic falls out of the end of all but about three connectors on the whole building so every place that has them installed ends up being no different than a building with non insulated throat.

I'm with you, somewhere along the way the guys sitting in their chairs (no offense to engineers) decided that compression were better even though the guys installing were tell them that they are not. We have been using steel set screw connectors and couplings for decades without any failure from the fittings.

On large EMT we're tightening them with an impact gun. How tight do you think a 4" compression EMT connector is with a guy trying to snug them up with two pairs of #480 Channellocks or a pair of chain wrenches? I can tell you not very tight.

 

[sameguy]

Do a search on fittings we talked about this before, steel ss for me, emt or galv/rig pipe, what was specked.
Commercial = emt mostly
Industrial = rig, imc,tray

 

[Eddie702]

@Cow,

I see die cast ss EMT connectors around here all the time. It's all the big box sells!!

As far a which one is better I prefer steel set screw but non of them are any good if not snugged up tight.

We had a state university just north of here that always specd compression. I think compression is slower to work with

 

[ActionDave]

I thought the point of the insulated throat, is to have the purpose of the plastic bushing integrated in the connector, so you don't need to separately supply it.

They get speced for all connectors on jobs. There is no reason for them on 3/4 and 1/2" pipe and when you get up into the larger wire sizes where you really need a bushed opening the plastic throat falls out, so if you care at all about your work you put a separate bushing on anyway. Boiler plate specs are so annoying.

 

[tom baker]

Yes I agree, esp for rough in SS are faster, small drill with #2 SD to tighten.
Most of the electrical I worked around was in pump stations, small concrete buildings, typically I saw steel compression, but again not large buildings. Some were EMT with FS boxes, but those were what the specs called for.

 

[ActionDave]

I'm with you, somewhere along the way the guys sitting in their chairs (no offense to engineers) decided that compression were better even though the guys installing were tell them that they are not.....

It's a down right shame too. I have a dream that one day the engineer and contractor will walk hand in hand to every job finding all the places they can make things better and not feel ashamed.

 

[tom baker]

It's a down right shame too. I have a dream that one day the engineer and contractor will walk hand in hand to every job finding all the places they can make things better and not feel ashamed.

Yes. And please remember we have Charlie, an engineer, who has
1) made many valuable contributions to this forum
2) knows a lot and admits when he doesn't
3) Author of "charlies law"

Is asking us for our opinions! So is that walking hand in hand in cyberspace?