How long to run and pull a feeder?

[LarryFine]

Me again. Situation: commercial building with existing suspended ceiling, 12' up, with bar-joist roof about 8' higher. I expect to use 3/8" all-thread, washers, and nuts, and Mineralac pipe hangers.

We need to run a 2.5" EMT with four 4-0's and a #4, all copper, about 6' up out of existing switchgear, about 80' horizontally above the ceiling, and about 8-10' down into a trough to feed a pair of panels.

The plans originally called for a main-breaker panel and a sub-fed one, but the owner already has two 200a panels, so I figured I'd split the 4-0's in the trough, and feed both panels with the same size.


1.) Is 3/8" all-thread large enough for this run, or would you recommend 1/2"?

2.) Working on a lift, how long ought it take two guys to run the EMT and pull and terminate the wire, including the trough?

3.) I figure on using split-bolts in the trough to feed the two panels. Alternate suggestions, and why?


"As always, if any of your IM team is caught or killed, the secretary will disavow any knowledge ofyour actions."

Danke!

 

[macmikeman]

Larry I have seen whole multi racks run with 3/8" rods and no problem. I assume you are going to make a rack and not just a single mineralac clamp right? Three days. Polaris taps, speed increase offsets the costs and just plain makes for a nicer job.

 

[chris kennedy]

2 men 2 days. I would use 3/8ths hardware also but Polaris instead of split bolts. Faster and easier.

As usual you did not mention if you will be working around equipment/furnishings. Is you plan to use a step ladder on the lift through the grid to reach the bar joist?

Also, extra hangers? Each one is good for 125lbs.

 

[chris kennedy]

Three days.

My first thought also. 2 years ago I would have figured for this to leave a cushion. These days we are looking to keep guys busy. I think if well organized Al and I could pipe it in one day and pull and terminate the next.

 

[macmikeman]

My first thought also. 2 years ago I would have figured for this to leave a cushion. These days we are looking to keep guys busy. I think if well organized Al and I could pipe it in one day and pull and terminate the next.

Ten years ago I would have said two days......

 

[growler]

Ten years ago I would have said two days......

Things were faster back then. :grin:

 

[bfrosty]

“If I had known I was going to live this long I’d have taken better care of myself.” It’s a quip attributed to, among others, Mark Twain, Mickey Mantle... Is it me or does it just hurt more? 3 days until I know more.

 

[LarryFine]

I assume you are going to make a rack and not just a single mineralac clamp right?

Actually, I figured just a single Minnie, rather than two rods, a 6" piece of strut, and a strut strap. Why?

Polaris taps, speed increase offsets the costs and just plain makes for a nicer job.

I agree. I was picturing the panel wires running to both panels in a single piece, with the split bolts in the middle. A 3-hole block would make it easier.

 

[LarryFine]

I would use 3/8ths hardware also but Polaris instead of split bolts. Faster and easier.

Word! D)

As usual you did not mention if you will be working around equipment/furnishings. Is you plan to use a step ladder on the lift through the grid to reach the bar joist?

Not if I can help it! (But, I might.) This area is in the back half of the space, and is not being remodeled. I thought aboud removing the parts of the grid in my way, and if I have to, putting them back after.

Also, extra hangers? Each one is good for 125lbs.

Presuming you're not talking to me, I also wonder how much the conductors and EMT weigh. I can't find it in the NEC. Anyone?

 

[LarryFine]

Okay, the concensus is 2 to 3 days for two people. I'll definitely err on the 3-day side, to include hanging the two panels and allow for ceiling hassles.

 

[daleuger]

Presuming you're not talking to me, I also wonder how much the conductors and EMT weigh. I can't find it in the NEC. Anyone?

Don't have my book handy but seems like I remember seeing weights on both in some of the tables in Chapter 9......a little math will definitely come into play too.

 

[iwire]

Single 3/8" rod with minnis would be what I would do. The weight will be no problem.



FWIW I would look into using MC cable for this but thats just me and my crazy fetish for cable.

4/0-4 copper MC is a stock item in my area.

Just make sure your help is as big as you are.

 

[chris kennedy]

to include hanging the two panels

Where does it say this in your OP? Now I'm definitely leaning toward 3 days.

 

[chris kennedy]

Just make sure your help is as big as you are.

Larry's charming wife?

 

[iwire]

BTW, the max safe load on typical 3/8" rod is at least 500 lbs.

 

[bfrosty]

81.4 lbs. per 100ft. of 4/0
12.7 lbs. per 100 ft. of 4

I'd say you are in the clear.

 

[iwire]

Larry's charming wife?

If I recall she looked to be all of 95 Lbs, 4/0-4 copper MC will shove her around like a rag doll. (No offense meant, it will shove me around if I am not paying attention)

 

[tkb]

I also wonder how much the conductors and EMT weigh. I can't find it in the NEC. Anyone?

http://www.mc2-ice.com/support/estref/popular_conversion_files/electrical.html

 

[bfrosty]

216 lbs. per 100 ft of 2.5 inch EMT

 

[bfrosty]

Nice little calculator

Nice little calculator

http://circuitcalculator.com/wordpress/2007/09/20/wire-parameter-calculator/