please answer a couple simple questions to end a disagreement between two electricians.Is there A maximum size conduit that can be used for branch circuiting?Is the maximum # of conductors allowed in any raceway 30 or the amounts listed in tables 9?also the maximum amount of 20 amp receptacles on a 20 amp circuit.Thank you
code Questions
- Thread starter m2oliva
- Start date
- Status
- Location
- Illinois
- Occupation
- retired electrician
Re: code Questions
A) No maximum size of conduit listed, but you have to derate for more than 3 current carrying conductors in the conduit. The 50% derating at the 10th current carrying conductor makes large raceways impracticable.
B) The maximum number of conductors is limited by Chapter 9, Table 1. Note again the derating issue.
C) In residential there is no code limit. In other occupancies you use the 180 va value to come up with a limit of 13 receptacles per 20 amp circuit.
Don
[ March 06, 2003, 07:28 PM: Message edited by: don_resqcapt19 ]
A) No maximum size of conduit listed, but you have to derate for more than 3 current carrying conductors in the conduit. The 50% derating at the 10th current carrying conductor makes large raceways impracticable.
B) The maximum number of conductors is limited by Chapter 9, Table 1. Note again the derating issue.
C) In residential there is no code limit. In other occupancies you use the 180 va value to come up with a limit of 13 receptacles per 20 amp circuit.
Don
[ March 06, 2003, 07:28 PM: Message edited by: don_resqcapt19 ]
russ
Senior Member
- Location
- Burbank IL
Re: code Questions
These are out of the Chicago code book, but their the same in the NEC.
18-27-348.7. Size.
(b) Maximum. The maximum size of tubing shall be the 4-in. electrical trade size.
18-27-346.6. Size.
(b) Maximum. Rigid metal conduit larger than 6-in. electrical trade size shall not be used.
Russ
[ March 06, 2003, 08:55 PM: Message edited by: russ ]
These are out of the Chicago code book, but their the same in the NEC.
18-27-348.7. Size.
(b) Maximum. The maximum size of tubing shall be the 4-in. electrical trade size.
18-27-346.6. Size.
(b) Maximum. Rigid metal conduit larger than 6-in. electrical trade size shall not be used.
Russ
[ March 06, 2003, 08:55 PM: Message edited by: russ ]
Re: code Questions
C) According to table 220-3(b). A dwelling unit has a load of 3VA per square foot. So, a 20A breaker could supply 800 square feet.
3VA x 800sq.ft=2400VA/120V=20A. Then you would have to determine how many recepts were required
in this area. Is it kitchen or other area?
C) According to table 220-3(b). A dwelling unit has a load of 3VA per square foot. So, a 20A breaker could supply 800 square feet.
3VA x 800sq.ft=2400VA/120V=20A. Then you would have to determine how many recepts were required
in this area. Is it kitchen or other area?
russ
Senior Member
- Location
- Burbank IL
Re: code Questions
I wonder what size receptacle box you need for 6" RMC.
I wonder what size receptacle box you need for 6" RMC.
mikeackley
Senior Member
- Location
- Washington
Re: code Questions
You cracked me up Russ. Best laugh I've had all day.
You cracked me up Russ. Best laugh I've had all day.
- Status