ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
Motion detectors and dimmers
by gfretwell. 09/20/18 04:02 PM
Extension cords
by annemarie1. 09/20/18 08:54 AM
Inspection camera help
by Bill Addiss. 09/19/18 10:50 PM
220/230/240V 60Hz Systems
by gfretwell. 09/16/18 12:37 PM
Acronis Backup 2017
by gfretwell. 09/16/18 12:46 AM
New in the Gallery:
Plug terminals
Housebilding DIY wiring
Who's Online Now
0 registered members (), 30 guests, and 26 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Simple question about voltage and current ratings #208706
02/07/13 06:10 PM
02/07/13 06:10 PM
P
piphomer  Offline OP
New Member
Joined: Feb 2013
Posts: 3
San Francisco, CA
Dear all,

I am new to the industry and new to this forum. So thanks for bearing with me on a simple question!

When a 3-phase electrical box, eg this one is rated at 400A, does that mean 400A per phase, or 400A total i.e. 133A per phase?

Also, this box for example is rated as 600V - does that mean phase to phase, or each phase to neutral?

Many thanks!!

-Phillip

Work Gear for Electricians and the Trades
Re: Simple question about voltage and current ratings [Re: piphomer] #208707
02/07/13 07:41 PM
02/07/13 07:41 PM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,289
Estero,Fl,usa
That is 400a per phase. The 600v is phase to phase.
For a 600v wye, l/n would be 347 as would be the wild leg of a center tapped 600v delta although I have never heard of doing it.
Typically you see 480v as the high end of "low voltage". (a multiple definition term itself)


Greg Fretwell
Re: Simple question about voltage and current ratings [Re: piphomer] #208708
02/07/13 10:03 PM
02/07/13 10:03 PM
P
piphomer  Offline OP
New Member
Joined: Feb 2013
Posts: 3
San Francisco, CA
Thanks!

So does that mean that for a 230V phase-phase (400V phase-neutral) system with a max current per phase of 160A, I actually can use a DH324NRK instead of the one in the previous link? Or do I have to go to the DH364NRK as I have 400V phase-phase so need the 600V capacity? Based on this cut sheet?

Thanks so much!

Re: Simple question about voltage and current ratings [Re: piphomer] #208717
02/07/13 11:39 PM
02/07/13 11:39 PM
G
gfretwell  Offline

Member
Joined: Jul 2004
Posts: 9,289
Estero,Fl,usa
If you have a 240v 3p with a 160a computed load the xx324xxx sounds like it is your panel with a 200a breaker using the appropriate conductors. If you had diversity and non continuous loads you could step down to 175a


Greg Fretwell
Re: Simple question about voltage and current ratings [Re: piphomer] #208724
02/08/13 07:11 AM
02/08/13 07:11 AM
T
Tesla  Offline
Member
Joined: Jun 2004
Posts: 1,273
Sacramento, CA
piphomer: You're too green to be an EE, C-10 or certified electrician.

At this scale of power use -- turn the matter over to professionals.

There are too many issues for you to 'get it right' over the Internet.


Tesla
Re: Simple question about voltage and current ratings [Re: Tesla] #208732
02/08/13 03:34 PM
02/08/13 03:34 PM
P
piphomer  Offline OP
New Member
Joined: Feb 2013
Posts: 3
San Francisco, CA
Agreed. Thanks.


Featured:

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

 

Member Spotlight
Attic Rat
Attic Rat
Bergen Co.,N.J. USA
Posts: 524
Joined: December 2003
Show All Member Profiles 
Top Posters(30 Days)
Admin 13
Trumpy 11
sparky 7
Popular Topics(Views)
249,346 Are you busy
187,280 Re: Forum
176,630 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.018s Queries: 15 (0.003s) Memory: 0.9774 MB (Peak: 1.1258 MB) Zlib enabled. Server Time: 2018-09-21 17:41:45 UTC