Forums | Home Repair | Home Improvement | Painting | Interior Decorating | Remodeling | Landscaping


Go Back   DIY Chatroom Home Improvement Forum > Home Improvement > Electrical

CLICK HERE AND JOIN OUR COMMUNITY TODAY...IT'S FREE!

Reply
 
Thread Tools Search this Thread Display Modes
Old 06-19-2009, 08:33 PM   #1
Newbie
 
Join Date: Jun 2009
Posts: 5
Share |
Default

ricerice57


hello guys, im new to site here .
im running a sub panel 80 ft. from main , am going to run 4 each #4 awg thhn wires and want to know if it is ok to run these in grey schedule 40plastic conduit, this will be inside the building up in the drop ceiling. also can i run this type of conduit inside the wall going down to the sub-panel?
thank you so much !
ricerice57 is offline   Reply With Quote
Old 06-19-2009, 09:13 PM   #2
Member
 
Join Date: Dec 2008
Location: Dayton Ohio Area
Posts: 670
Default

ricerice57


What is the type of wire you are running?

You can run a smaller ground wire than #4. I don't know which size is acceptable, someone else here will chime in.

Yes, you can use sCH PVC 40 that is rated for electrical.
__________________
-Andrew
DIY hobbiest
AndrewF is offline   Reply With Quote
Old 06-19-2009, 09:26 PM   #3
Member
 
Join Date: Jul 2008
Location: Iowa
Posts: 1,543
Default

ricerice57


What may the amperage be of the sub panel?
rgsgww is offline   Reply With Quote
Old 06-19-2009, 09:29 PM   #4
Member
 
Join Date: Jan 2009
Location: South of Boston, MA
Posts: 17,248
Default

ricerice57


How big is your main panel?
Have you done a whole house electric calc?
Not sure on #4 wire, I ran #6 for a 60a

How much power do you need?
Scuba_Dave is offline   Reply With Quote
Old 06-19-2009, 09:48 PM   #5
Newbie
 
Join Date: Jun 2009
Posts: 5
Default

ricerice57


main panel is 200 amp. I am planning on useing a 100 amp breaker to supply the sub panel and will have 8each 20 amp breakers in sub., at no time will there ever be all 8 circuits drawing full load at . worst case 24,000 watts divided among the 8 breakers no more
ricerice57 is offline   Reply With Quote
Old 06-19-2009, 10:36 PM   #6
DIY'r
 
ScottR's Avatar
 
Join Date: Oct 2008
Location: Hicksville, NY (Yes, it's an actual town).
Posts: 520
Default

ricerice57


Yes, the grey sch. 40 PVC is OK to use for the entire run.

#4 copper is OK for 100A, and you can use a #10 bare or green insulated wire for the ground.

Quote:
worst case 24,000 watts divided among the 8 breakers no more
That's a full 100A @ 240V.. If you are planning on drawing more than 80A for more than 3 hours then you will have to up-size your wiring/panel. (Continuous loads are calculated at 125%).

Just curious, what are you running that's going to draw 24KW? (Or did you just mean "don't worry about it, I'm good"?)
ScottR is offline   Reply With Quote
Old 06-19-2009, 10:50 PM   #7
Newbie
 
Join Date: Jun 2009
Posts: 5
Default

ricerice57


we are running hair blowers on 4 rows of workstations i was calculating 16 hairblowers at 1500 watts each running all at the same time lol this will never happen in reality maybe 5 dryrers running at the same time and only for 5-10 mins each
thanks guys your really a big help
ricerice57 is offline   Reply With Quote
Old 06-20-2009, 04:50 AM   #8
Electrical Contractor
 
kbsparky's Avatar
 
Join Date: Sep 2008
Location: Delmarva
Posts: 3,352
Default

ricerice57


Quote:
Originally Posted by ScottR View Post
#4 copper is OK for 100A, and you can use a #10 bare or green insulated wire for the ground....
Not quite. You will need to use #3 copper for the hot lines for a 100 Amp panel. The exception in section 310.15(B)(6) that allows one to use a #4 would not apply here.

Also, a #8 copper ground wire would be the minimum requirement.

In such a scenario, we would use (2)#3, (1)#4, and (1)#8 wires.
kbsparky is offline   Reply With Quote
Old 06-20-2009, 11:35 AM   #9
Newbie
 
Join Date: Jun 2009
Posts: 5
Default

ricerice57


Thank you so much kbsparky this helps me out tremendously as i really want this to be a proffesional installation and in a case like this where money is tight what your telling me will save me quite a bit in contractor fees alone.
I love you guys , your all a great help and service to the community !
ricerice57 is offline   Reply With Quote
Old 06-20-2009, 11:51 AM   #10
Licensed Electrical Cont.
 
Speedy Petey's Avatar
 
Join Date: Feb 2004
Location: NY State
Posts: 6,676
Default

ricerice57


Quote:
Originally Posted by kbsparky View Post
Not quite. You will need to use #3 copper for the hot lines for a 100 Amp panel. The exception in section 310.15(B)(6) that allows one to use a #4 would not apply here.
Not quite. In my area, and may others, we ARE allowed to use 310.15(B)(6) for feeders in a residence.


I have an issue here though.
Rice, you say: "we are running hair blowers on 4 rows of workstations".
Is this a commercial setting? If so many things change. The most important is that you likely should NOT be doing this work yourself unless you are licensed, insured and qualified to do so.
__________________
Sometimes I feel like if I answer any more questions it is like someone trying to climb over a fence to jump off a bridge and me giving them a boost.
Answers based on the 2008 & 2011 NEC. If you're on the '14 already I feel sorry for you.
Speedy Petey is online now   Reply With Quote
Old 06-21-2009, 04:22 AM   #11
Newbie
 
Join Date: Jun 2009
Posts: 5
Default

ricerice57


speedy pete I started to remove the old wires today and could not believe my eyes when i seen what a local licenced contractor did in up in the drop ceiling he took 6 circuits and ran them all to 1 4x4 box with 2 lines coming in each on a 20 amp breaker putting 3 lines to each breaker, all 6 of these circuits need to be on their own breaker. this guy really did a bad job and now i gotta fix his mess, no im not licenced but i have been in the industrial maint. industry for more than 20 years trouble shooting 460 3 phase 240 3 phase metal working machinery and food processing equipment. and i have built some very impressivemetal working equipment as well, so you see i am very knowlegable as far as running a simple sub-panel goes i just dont know the code as well as contractors do or supposed to know in this fools case.
thank you very much for your help and expertise in helping me out .

Last edited by ricerice57; 06-21-2009 at 04:25 AM.
ricerice57 is offline   Reply With Quote
Reply


Thread Tools Search this Thread
Search this Thread:

Advanced Search
Display Modes

Posting Rules
You may not post new threads
You may not post replies
You may not post attachments
You may not edit your posts

BB code is On
Smilies are On
[IMG] code is On
HTML code is Off
Trackbacks are Off
Pingbacks are Off
Refbacks are Off





Top of Page | View New Posts

Copyright © 2003-2014 Escalate Media. All Rights Reserved.