ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
AreMetal Ladders Ever OK For Electrical Work?
by HotLine1. 01/22/18 07:31 PM
Photocell
by twh. 01/22/18 05:06 PM
VDE 0100 to introduce AFCIs
by sparky. 01/20/18 05:09 PM
MRI LED lights dimmer control replacement - wow!
by Potseal. 01/19/18 08:52 PM
New in the Gallery:
Housebilding DIY wiring
SE cable question
Who's Online Now
0 registered members (), 6 guests, and 8 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
4160 volt conductor rateings #91852
02/09/05 11:20 AM
02/09/05 11:20 AM
Y
Yoopersup  Offline OP
Member
Joined: Mar 2003
Posts: 840
Michigan
Table 310.73 2001-5000 volts M.V.105.
500kcmil =530 amps for derateing 475 for terms(110.40). As i see it no derateing for a bank of pipes in open air. Thus 2000 amp requirement = 4 sets 530x4=2120
or 4 sets 475= 1900 amps.
240.101 states fuse can be 3 times conductors ampacity breaker or electronically actuated fuse up to 6 times.


So as I see it conductors must be rated for the ampacity of the true load. Over current protection can be higher then conductor rateings.
The highter amps rateing 105% for derateing only the 90% rateing for terms.
so if load is 1900 amps or below 500s can be used ,fused at 2000 amps.

2017 / 2014 NEC & Related Books and Study Guides
Re: 4160 volt conductor rateings #91853
02/10/05 01:28 PM
02/10/05 01:28 PM
B
Bob  Offline
Member
Joined: Feb 2002
Posts: 182
Mobile, AL, USA
Yoopersup
What is the load your are working with?

Re: 4160 volt conductor rateings #91854
02/11/05 07:58 AM
02/11/05 07:58 AM
Y
Yoopersup  Offline OP
Member
Joined: Mar 2003
Posts: 840
Michigan
Last sentence says 1900 amps or below.


Featured:

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

 

Member Spotlight
mxslick
mxslick
Atomic City, ID USA
Posts: 803
Joined: October 2004
Show All Member Profiles 
Top Posters(30 Days)
Admin 21
sparky 15
Potseal 15
Popular Topics(Views)
243,597 Are you busy
180,402 Re: Forum
170,868 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.011s Queries: 14 (0.003s) Memory: 0.9488 MB (Peak: 1.0725 MB) Zlib enabled. Server Time: 2018-01-23 07:46:54 UTC