ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
It's been an interesting career
by Marienauripod - 05/23/22 12:21 AM
Run Cap subsitution question. Two vs. one
by LarryC - 05/20/22 09:01 PM
Material shortages???
by NORCAL - 05/02/22 04:12 PM
New in the Gallery:
240/208 to a house
240/208 to a house
by wa2ise, October 9
Now you know.
Now you know.
by Tom_Horne, September 7
Who's Online Now
0 members (), 43 guests, and 11 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#89878 10/22/04 02:07 PM
Joined: Feb 2004
Posts: 494
M
Member
Hi,
Any tips on connecting a 400A Generator for temporary power?

I appreciate any replies.

-regards

Mustang

Stay up to Code with the Latest NEC:


2020 NEC & Related Reference & Study Guides
2020 NEC & Related Reference & Study Guides
Pass Your Exam the FIRST TIME with these Exam Prep Combos:
 

>> Master Electrician Exam Prep     >> JourneyMan Electrician Exam Prep
 

#89879 10/26/04 06:44 PM
Joined: Mar 2001
Posts: 345
T
Member
If the set up will be temporary I would tie the generator into the Service Disconnecting means load side wiring if possible. This presumes that the generator has a main breaker that will serve in place of the Service Disconnecting Means. It also presumes that the service disconnecting means is a separate piece of equipment that is connected to the load by field installed wiring.

If, on the other hand, the service equipment is some sort of combined main breaker and panel equipment then you will need to use a double block and break technique to isolate the building from the utility power. If the building is supplied through a 400 ampere meter socket than you would open the service disconnect, pull the meter, blank off the meter socket and disconnect the meter load wiring from the service disconnecting means. You would then blind off the meter load wiring with insulating materials. That makes the line side terminals of the service disconnecting means available for connecting the generator to. Since meter sockets in the four hundred ampere size are often equipped with shunts you will have to secure the shunt in the open position. The same lever is often used to release the meter jaws and engage the shunt bypass. These have to be operated to the open position after having removed the meter. If the service is larger than four hundred amperes then removing the meter will not deenergize the service disconnecting means line side terminals. So check for voltage every step of the way.
--
Tom H


Tom Horne

"This alternating current stuff is just a fad. It is much too dangerous for general use" Thomas Alva Edison
#89880 10/26/04 08:14 PM
Joined: Feb 2004
Posts: 494
M
Member
Hi,
Thanks for the reply. You were right when you said it is a temporary one and the gen set has it's own OCPD and it also has a multi tap transformer to give several different voltage configurations.

We will tie the feeder from the gen set ocpd to a gutter that feeds several exisitng MB panels. we will use the existing ground rod to ground the system.

I am assuming no other path to ground is allow so as not to create a difference of potential on the gen set xfmr?

i have seen portable welders that if not grounded properly can be very dangerous.

no need to ground to building steel if the building is bonded through the first disconnect/panel to the gec?

thanks for the replies..

-regards

greg


Link Copied to Clipboard
Featured:

Tools for Electricians
Tools for Electricians
 

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
Theelectrikid
Theelectrikid
Levittown, PA
Posts: 811
Joined: April 2004
Top Posters(30 Days)
LarryC 3
NORCAL 2
Popular Topics(Views)
291,336 Are you busy
223,828 Re: Forum
209,228 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.5