Drywall ceiling penetration with conduit for lift?

[Dr_Pippin]

Need to route power from my attic down to my 2 post lift. Looking for suggestions on penetrating my drywall ceiling with conduit in such a way as to allow the conduit to move a little if the post should move without damaging the surrounding drywall. Lift is really close to the ceiling, so I didn’t think relying on conduit flex is a great idea. Is there any sort of box or conduit connection that would allow a little movement?

Follow up question, is PVC conduit ok or do I need to consider EMT? What are the pros/cons of choosing one over the other?

 

[The Cobbler]

do you need it to be in conduit or can you use MC wire

 

[Dig Doug]

 

[infinkc]

I have an outlet box installed in my ceiling with a twist lock. Have the cord attached to that going to the lift. It’s tied to the lift on top so it’s secure.

 

[TurnipTruck]

I used the flex mentioned above to isolate any hoist movement from damaging the drywall.

 

[alfredeneuman]

A lift is one of the few things that's allowed to use portable cord without a receptacle.
It can come directly from the j-box to the lift.

 

[mm08822]

A lift is one of the few things that's allowed to use portable cord without a receptacle.
It can come directly from the j-box to the lift.

Also not using a recept will eliminate a gfci requirement.

A 120vac lift may require a "high magnetic" rated cb, available in 15 @ 20A single pole, to eliminate random cb tripping on startup.
If wired for 240 vac, then startup tripping shouldn't be an issue.

 

[wssix99]

Flexible metallic conduit works great. It looks like you already have boxes in your ceiling. Here's how I tied into mine.





I ran my flex conduit over to the limit switch box and then just used the cord that came with the lift to handle the wiring between it and the
switch.

The top plate is non-structural and easy to tap screws into. You can also put screws into the main posts. When I do that, I'm careful to avoid zones where blocks ride inside the columns. I also try to select screws that do not penetrate the column completely.

 

[dave*99]

Flexible metallic conduit works great. It looks like you already have boxes in your ceiling. Here's how I tied into mine.





I ran my flex conduit over to the limit switch box and then just used the cord that came with the lift to handle the wiring between it and the
switch.

The top plate is non-structural and easy to tap screws into. You can also put screws into the main posts. When I do that, I'm careful to avoid zones where blocks ride inside the columns. I also try to select screws that do not penetrate the column completely.

I did similar with a flexible Sealtite whip of the type used for an AC condensing unit. Readily available at the big box store.

 

[Dr_Pippin]

Thanks everyone - and especially thanks for the photos. I'm very visual, especially with things I don't have much experience with, so the photos were super helpful. I really like the flexible conduit suggestions, and that's what I'll be doing as well. I picked up a 6' length of liquid-tight conduit that I'll run down the post, mount a 2-gang junction box, and do the hardwired connections to the lift motor in that box. In that same junction box I'll have a 20 amp outlet on a dedicated run from the sub panel. I'll share some pics when I get it finished. Thanks!

 

[dave*99]

Thanks everyone - and especially thanks for the photos. I'm very visual, especially with things I don't have much experience with, so the photos were super helpful. I really like the flexible conduit suggestions, and that's what I'll be doing as well. I picked up a 6' length of liquid-tight conduit that I'll run down the post, mount a 2-gang junction box, and do the hardwired connections to the lift motor in that box. In that same junction box I'll have a 20 amp outlet on a dedicated run from the sub panel. I'll share some pics when I get it finished. Thanks!

I have similar. And in that J box on the lift right near the motor I have a motor rated 2 pole disconnect switch. So I can kill power if the lift push button sticks etc.

 

[Dr_Pippin]

I have similar. And in that J box on the lift right near the motor I have a motor rated 2 pole disconnect switch. So I can kill power if the lift push button sticks etc.

Do you have a link to that switch? Seems like a really good idea. I had looked at disconnects, but they all seemed like the ones for A/C units in large boxes that I didn't really want to mount on my lift.

 

[dave*99]

Do you have a link to that switch? Seems like a really good idea. I had looked at disconnects, but they all seemed like the ones for A/C units in large boxes that I didn't really want to mount on my lift.

Leviton makes a few. Here is one type:

https://www.amazon.com/Leviton-MS302-DS-Disconnect-Industrial-Non-Grounding/dp/B002MPQ51O/?tag=atomicindus08-20

 

[Dr_Pippin]

Flexible metallic conduit works great. It looks like you already have boxes in your ceiling. Here's how I tied into mine.





I ran my flex conduit over to the limit switch box and then just used the cord that came with the lift to handle the wiring between it and the
switch.

The top plate is non-structural and easy to tap screws into. You can also put screws into the main posts. When I do that, I'm careful to avoid zones where blocks ride inside the columns. I also try to select screws that do not penetrate the column completely.

Where did you get that cover plate? Or did you make it? I've been trying to locate that plate so I could replicate your ceiling connection, but haven't been able to find it. Figuring I'll have to drill it, but I know I'll probably crack at least three cover plates before I succeed.

 

[alfredeneuman]

crack at least three cover plates before I succeed.

This one is guaranteed not to crack (It's metal)

Commercial Electric 1-Gang Blank Metallic Weatherproof Cover, White WBC100W - The Home Depot

Provide an essential and ultimate addition to your electrical application with the help of this Commercial Electric White 1-Gang Weatherproof Blank Cover.

www.homedepot.com

 

[wyliesdiesels]

Need to route power from my attic down to my 2 post lift. Looking for suggestions on penetrating my drywall ceiling with conduit in such a way as to allow the conduit to move a little if the post should move without damaging the surrounding drywall. Lift is really close to the ceiling, so I didn’t think relying on conduit flex is a great idea. Is there any sort of box or conduit connection that would allow a little movement?

Follow up question, is PVC conduit ok or do I need to consider EMT? What are the pros/cons of choosing one over the other?

Flex should work just fine.

Or go with cord and plug or hardwired cord.

No need to reinvent the wheel

 

[wyliesdiesels]

Thats overkill since its indoors. FMC will work just fine

 

[Dr_Pippin]

This one is guaranteed not to crack (It's metal)

Commercial Electric 1-Gang Blank Metallic Weatherproof Cover, White WBC100W - The Home Depot

Provide an essential and ultimate addition to your electrical application with the help of this Commercial Electric White 1-Gang Weatherproof Blank Cover.

www.homedepot.com

That’s what I went with - no idea why I didn’t consider metal!

Cover plate is drilled, installed, and cable running through it. Just need to mount the junction box and then figure out the length of conduit to connect the two points. Going to have to buy a tap for threading the holes I drilled in the post for mounting purposes. Disconnect switch is scheduled to be delivered tomorrow, and hopefully I’ll have free time Friday to wrap up the install and get a car into the air by this weekend.

 

[wyliesdiesels]

why do you have 12/2 and 10/2 running thru that?

 

[dave*99]

Use THHN/THWN wire. Red and black 10 gauge and red and white 12 gauge plus a green ground wire.

Should look like this with 2 more conductors

 

[mike93lx]

why do you have 12/2 and 10/2 running thru that?

All the effort and then romex running like that...

 

[wyliesdiesels]

All the effort and then romex running like that...

No kidding

 

[Dr_Pippin]

why do you have 12/2 and 10/2 running thru that?

Use THHN/THWN wire. Red and black 10 gauge and red and white 12 gauge plus a green ground wire.

Should look like this with 2 more conductors

All the effort and then romex running like that...

You guys aren't wrong that there were other installation options, but as with everything I've done with this garage build it has been an evolving installation. My original plan was a junction box in the ceiling and just running the lift's wiring straight to that box for the connections - hence having run romex from my sub panel on the other side of the garage like I did for every other outlet. My plan subsequently evolved into wanting an outlet accessible on the lift, so conduit running down from the ceiling became the new choice. Which then further morphed with the addition of a disconnect switch for the lift in that same box. I'd already run Romex from the sub panel into the attic and finished the drywall and paint, so no way was I going to be changing the wiring in there. So what if I've got Romex running in 5' of conduit now?

 

[dave*99]

You guys aren't wrong that there were other installation options, but as with everything I've done with this garage build it has been an evolving installation. My original plan was a junction box in the ceiling and just running the lift's wiring straight to that box for the connections - hence having run romex from my sub panel on the other side of the garage like I did for every other outlet. My plan subsequently evolved into wanting an outlet accessible on the lift, so conduit running down from the ceiling became the new choice. Which then further morphed with the addition of a disconnect switch for the lift in that same box. I'd already run Romex from the sub panel into the attic and finished the drywall and paint, so no way was I going to be changing the wiring in there. So what if I've got Romex running in 5' of conduit now?

If you have a junction box behind the cover plate (or add an old work box) you can splice into THHN.
The Romex you have will exceed the fill limit in conduit.
It’s an easy fix to make it right.

 

[Dr_Pippin]

If you have a junction box behind the cover plate (or add an old work box) you can splice into THHN.
The Romex you have will exceed the fill limit in conduit.
It’s an easy fix to make it right.

Ugh, I forgot about fill size. Dammit. Just did some math and a little perusing of the NEC and looks like I'd have to use 1&1/4" conduit to have the proper cross-sectional space for my wires. And of course I only bought 3/4". Damn. Ok, off to THHN I go. Thank you for setting me straight.

Guess I should ask now... Anything funky with connecting single strand Romex conductors to THHN? Just a simple wire nut? And I assume no reason to not use solid THHN for 10 and 12 gauge conductors?

 

[dave*99]

Ugh, I forgot about fill size. Dammit. Just did some math and a little perusing of the NEC and looks like I'd have to use 1&1/4" conduit to have the proper cross-sectional space for my wires. And of course I only bought 3/4". Damn. Ok, off to THHN I go. Thank you for setting me straight.

Guess I should ask now... Anything funky with connecting single strand Romex conductors to THHN? Just a simple wire nut?

Wire nut is fine.

 

[Dr_Pippin]

Wire nut is fine.

And any reason to not use solid core THHN? I've never bought the stuff before, not sure if there's any difference in use or even cost.

 

[dave*99]

And any reason to not use solid core THHN? I've never bought the stuff before, not sure if there's any difference in use or even cost.

Solid is fine.

 

[wyliesdiesels]

You guys aren't wrong that there were other installation options, but as with everything I've done with this garage build it has been an evolving installation. My original plan was a junction box in the ceiling and just running the lift's wiring straight to that box for the connections - hence having run romex from my sub panel on the other side of the garage like I did for every other outlet. My plan subsequently evolved into wanting an outlet accessible on the lift, so conduit running down from the ceiling became the new choice. Which then further morphed with the addition of a disconnect switch for the lift in that same box. I'd already run Romex from the sub panel into the attic and finished the drywall and paint, so no way was I going to be changing the wiring in there. So what if I've got Romex running in 5' of conduit now?

the thing is, NM-b is not flexible. you shouldve used either cordage plugging into a receptacle, or THWN in FMC.

 

[Dr_Pippin]

the thing is, NM-b is not flexible. you shouldve used either cordage plugging into a receptacle, or THWN in FMC.

The NM-B had to make a single 45° turn and then run straight in 5’ of conduit. It was simple to pass through the 45° fitting, no harder than passing through the hole in the back of the junction box in the ceiling. I understand now about fill limits and why I shouldn’t have planned running Romex in the conduit (although actually it would have been fine doing Romex inside conduit if I’d used a it larger conduit, just didn’t plan for it). If I was trying to pull wire through a long run of conduit with a bunch of 90° bends, it would have been a very different story.