pulling THWN wire through long conduit, which type to use, how difficult ?

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What is the nature of the physical damage that this conduit is likely to experience? Lawnmower? Car? Projectile firewood? Nothing?
 
What is the nature of the physical damage that this conduit is likely to experience? Lawnmower? Car? Projectile firewood? Nothing?
Nothing specific. It's just that it's at lower-leg level on the front face of a 6x6 at the end of the catwalk to the house. Pretty sure that's "subject to damage" or whatever the NEC wording is. And for such locations, pretty sure Sch40 PVC is not code-compliant. But people here seem to think it's largely ignored, so maybe I won't worry about it.

Actually, it's liquid-tight that is coming up the edge of the 6x6 now. Was thinking I should at least replace that stretch with conduit, and if conduit, why not Sch80 ? Except I'm too cheap to pay $30-40 for a 10ft stick of 1" Sch80 and only use 2-3ft.

I think maybe the simplest thing to do (besides nothing) is just to surround the liquid-tight with a piece of EMT.
 
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Sure, if it gives you peace of mind, sleeve the conduit inside a larger piece of conduit. Or protect it some other way. "Subject to damage" is subjective. You are the inspector, so just ask yourself what you think will be adequate to prevent it from getting broken.
In reality, sch40 PVC is very tough stuff and unless it's right along a driveway where you could smack it with a car, I wouldn't be worried about it.
 
What is the nature of the physical damage that this conduit is likely to experience? Lawnmower? Car? Projectile firewood? Nothing?
Careless or inexperienced hands on the controls of a zero turn mower, weed trimmers, etc.
 
Careless or inexperienced hands on the controls of a zero turn mower, weed trimmers, etc.
Yeah, weed-trimmer, that's a good thought. Wife uses it a lot.
 
if you are going to sleeve the liquid tite in emt why not just use the emt without the liquid tite? besides if you use any type of metal to carry the conductors it will have to be bonded with the ground. i hit my pool pvc every time i weedwack and don't have a problem.
 
if you are going to sleeve the liquid tite in emt why not just use the emt without the liquid tite?
I don't have any experience with EMT (except as deck railing). So I just can't figure out how to transition from the liquid-tight to EMT. I don't see any female adapters for EMT listed. (I'd still have EMT coming from where the PVC ends under the catwalk, to negotiate the weird angles coming up towards the EVSE. But I'd cut it off and transition to EMT, if I could figure out how).
 
besides if you use any type of metal to carry the conductors it will have to be bonded with the ground.
Surely if I surround PVC with EMT for protection, that EMT doesn't need to be grounded.
 
So I just can't figure out how to transition from the liquid-tight to EMT. I don't see any female adapters for EMT listed. (I'd still have EMT coming from where the PVC ends under the catwalk, to negotiate the weird angles coming up towards the EVSE. But I'd cut it off and transition to EMT, if I could figure out how).
See post 99...
 
Couple the liqi tight fitting to an EMT box connector with a female x female conduit coupler
I can't find such a thing. Unless you mean a compression type, but do those work for liquid-tight ? As best I can tell, liquid-tight doesn't have a standard O.D. but is usually larger than EMT.


Also, the EMT conduit bodies seem to have a socket with a set-screw. So I'd transition from liquid-tight to a short piece of EMT with the double-female compression thing ? Or maybe the liquid-tight can go straight into the set-screw opening in the LB ? Sorry to be dense ...
 
I can't find such a thing. Unless you mean a compression type, but do those work for liquid-tight ? As best I can tell, liquid-tight doesn't have a standard O.D. but is usually larger than EMT.


Also, the EMT conduit bodies seem to have a socket with a set-screw. So I'd transition from liquid-tight to a short piece of EMT with the double-female compression thing ? Or maybe the liquid-tight can go straight into the set-screw opening in the LB ? Sorry to be dense ...
Take the nut and oring off, connect it to the liqi tight fitting with a simple female x female connector...use pipe dope on it for rain tightness
 
Take the nut and oring off, connect it to the liqi tight fitting with a simple female x female connector...use pipe dope on it for rain tightness
leave the oring on don't use pipe dope it is not code compliant
 
with emt you always use compression fittings outside never use the screw type of fitting they are not waterproof
fittings like these

https://www.homedepot.com/p/Carlon-3-4-in-PVC-Female-Adapter-E942ER-CTN/100404044




anything that is metal on that run has to be bonded with the ground

like a pool. inground the metal stairs has to be bonded even tho the ladder or stairs or hand rail is across the other side of the pool if it's metal it has to be bonded with the motor that is a weird for instance but i just did one 😁
 
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I would not be putting liquid tight inside of EMT. Don't be creative with electrical work, creativity is rarely a recipe for code compliance.

Sch.80 is recommended for ground penetrations and any place where damage is likely, but as noted, almost no one actually carries of uses the stuff. Nearly all electricians just run sch.40 PVC for their ground penetrations, and you'll likely be fine for that. In cases where repair is neigh-on impossible, I transition to stainless rigid for ground penetration, such as I just did with my new patio. Sch.40 PVC below grade, female NPT adapter, then stainless rigid for the patio penetration, with an LB topside.

As to how to transition from PVC to liquid tight, I thought you already had that done? Usual method is female NPT adapter on PVC end with a male liquid tight adapter on liquid tight end.

edit: just managed to find a photo of this, from before I poured concrete. See red circle, lower left.

IMG_0090.JPG
 
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As to how to transition from PVC to liquid tight, I thought you already had that done? Usual method is female NPT adapter on PVC end with a male liquid tight adapter on liquid tight end.
Yes, I do, as described.

I'm going to stop worrying about using Sch80 PVC or EMT. Only other question: right now, after I transition to liquid-tight, I bring it all the way from under the catwalk and then up the edge of the 6x6 to the EVSE. Does it make sense to transition back to PVC before I come up the 6x6 (basically using the liquid-tight as a flexible elbow in the PVC run) ? IOW, is Sch40 PVC more or less durable than liquid-tight ?
 
I guess that depends on durability against what? PVC is pretty durable except when frozen (shatter impact) and abrasion (wear-thru). Liquid tight will never shatter or fail from blunt impact, but can be cut or wear thru.

I’ve seen so many countless swimming pool installers run them side by side, that this is what I did on my own recent panel install. I have 1” and 3/4 sch.40 PVC for mains and pool light, but 3/4” amd 1/2” liquid tight for heat pump and filter pump. Liquid tight is zip-tied to mains PVC with big black UV resistant zip ties.

Primary enemy for wear thru is string trimmer, and primary enemy for impact is mower, so just make ground penetration area a mulch bed or stones, not grass.
 
Here's a thought. The O.D. of my 1" conduit is 1.315". The I.D. of 1-1/4" is 1.360". Close enough fit nicely together, with some solvent. And I have some 1-1/4" lying around. So fab my own Schedule 80 !! This doesn't have the grounding issues of sleeving it with metal. Nor, I suspect, does it look as fishy to inquiring eyes.
 
You would need to leave the 1" longer on both ends than the 1-1/4", to work with fittings, but I agree it would be tough to damage that. Only potential issue I can even imagine is water getting between the two and possibly freezing, but I suspect that would never cause actual damage.

Then again, I'll repeat what a past commercial electrician once told me, "don't get creative".
 
So I found this stuff that I liberated from Spectrum when they were burying cable in our 'hood. They run it first and encase the actual cable inside it. Seems tough as nails.

So I just ran it up to above weed-eater and boot height, and then down to where the liquid-tight bends back under the catwalk to connect to the PVC conduit.

PXL_20230818_202942420.jpg PXL_20230818_192913192.jpg
 
So I found this stuff that I liberated from Spectrum when they were burying cable in our 'hood. They run it first and encase the actual cable inside it. Seems tough as nails.

So I just ran it up to above weed-eater and boot height, and then down to where the liquid-tight bends back under the catwalk to connect to the PVC conduit.

View attachment 314606 View attachment 314607
never seen the stuff before
 
I spent a good 12 hours digging conduit today, after a fence company ignored my markings and requested fence location, instead putting the damn thing right on the red line that indicated "high voltage / no dig". No kidding, they punched thru the conduit in at least two locations, and destroyed the wiring inside.

I had the intended track painted in yellow, and even marked the proposed post locations with flags, but for some reason they moved the whole thing over 5-6 feet from that location and dug right on top of the red line designating conduit.

Long day, started digging around 7am, went until dark, and then made the Lowes run to pick up the required repair materials.
 
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Crappy day, sorry.
 
I spent a good 12 hours digging conduit today, after a fence company ignored my markings and requested fence location, instead putting the damn thing right on the red line that indicated "high voltage / no dig". No kidding, they punched thru the conduit in at least two locations, and destroyed the wiring inside.

I had the intended track painted in yellow, and even marked the proposed post locations with flags, but for some reason they moved the whole thing over 5-6 feet from that location and dug right on top of the red line designating conduit.

Long day, started digging around 7am, went until dark, and then made the Lowes run to pick up the required repair materials.
that sucks you are doing their job. i hit a romex in the ceiling and replaced and repaired it just like they were supposed to. they damaged it.