ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
Pull out fuse panel?
by wa2ise. 12/14/18 05:09 PM
Video door bell causing chime activation of coil
by gfretwell. 12/10/18 12:35 AM
Conduit fill Calculations
by gfretwell. 12/08/18 08:39 PM
Swimming Pool question
by HotLine1. 12/05/18 12:37 PM
Tingle off the water spigot
by rmiell. 11/30/18 01:03 PM
New in the Gallery:
What is this for?
Plug terminals
Who's Online Now
0 registered members (), 7 guests, and 25 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Feeder Taps #101223
02/26/07 03:33 PM
02/26/07 03:33 PM
R
Reel-Break  Offline OP
Member
Joined: Apr 2002
Posts: 178
nc
We`re working in a plant wiring a machine and they have in switch gear room a 600 amp breaker 3 500`s feed a JB from there a set of 3/0`s tapped to a 225 amp breaker and then another set of 3/0`s tapped to 200 amp. Is all well with this? I read the feeder tap rules but wasn`t sure about the loading of the main 600 amp is this considered cont load or non or does this effect calculations? Do you figure .80 which would be rughly 480 amps continuous? Thanks for some insight. These are textile machines many motors.

2017 / 2014 NEC & Related Books and Study Guides
Re: Feeder Taps #101224
02/26/07 04:18 PM
02/26/07 04:18 PM
R
resqcapt19  Offline
Member
Joined: Nov 2000
Posts: 2,148
IL
The load calculations and the tap rules are two different issues. This installation appears to comply with 240.21(B) assuming the 3/0s are 25' or less. You would have to do a load calculation as to the total loads, however with only 425 amps of overcurrent protection on the taps, there is no way that the 600 amp circuit is overloaded.
don


Don(resqcapt19)

Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
electure
electure
Fullerton, CA USA
Posts: 4,276
Joined: December 2000
Show All Member Profiles 
Top Posters(30 Days)
Popular Topics(Views)
252,207 Are you busy
189,184 Re: Forum
178,868 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.019s Queries: 14 (0.004s) Memory: 0.9427 MB (Peak: 1.0614 MB) Zlib enabled. Server Time: 2018-12-15 06:51:07 UTC