ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat
Recent Posts
Increasing demand factors in residential
by gfretwell - 03/28/24 12:43 AM
Portable generator question
by Steve Miller - 03/19/24 08:50 PM
Do we need grounding?
by NORCAL - 03/19/24 05:11 PM
240V only in a home and NEC?
by dsk - 03/19/24 06:33 AM
Cordless Tools: The Obvious Question
by renosteinke - 03/14/24 08:05 PM
New in the Gallery:
This is a new one
This is a new one
by timmp, September 24
Few pics I found
Few pics I found
by timmp, August 15
Who's Online Now
0 members (), 260 guests, and 20 robots.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
#26099 05/29/03 11:52 PM
Joined: Jan 2002
Posts: 324
A
Member
Sorry i havent been around much, these 14 hour days are killing me, but i guess it beats the alternative. Anyway, here's my question.

I am doing a small shopping center that will have five seperate UG services (three 200A 3ph, one 400A 3ph and one 200A 1ph). The poco would not allow me to set each service at the back of the stores due a detention pond that runs behind half of the building. So i have to pipe to the xfmr pad and and set the cans in a bank.

With all these services having less than a foot between them, how should i handle my driven rod? Drive one per service even though the rods would be about 40" apart, or drive two rods or more and form a grid keeping them 6' apart and thermo-weld them together.

I dunno, never had to group my meters so close before.

#26100 05/30/03 01:24 AM
Joined: Apr 2002
Posts: 558
C
Member
arseegee

Your going to supply this building with 5 sets of underground service conductors? If so I feel this would be a violation of 230.2 and also surprised your POCO is willing to do this. You should bring one set of service conductors to the building and then tap off for each meter.

You do not need to drive a separate ground rod for each service. You are required to connect each of these services to the same grounding electrodes. 250.58

Why don't you use a 3 section switchboard? Pull Section - 400A Meter Section - 4 200A Meters Section

Curt

[This message has been edited by caselec (edited 05-30-2003).]


Curt Swartz
#26101 05/30/03 09:17 PM
Joined: Jan 2002
Posts: 324
A
Member
Curt, this is a multiple occupancy building with 2hr firewall seperations between the buildings. I wanted to install a trough and tap the services individually but the POCO engineer is requiring me to pipe each lateral to the xfmr. There is no winning an arguement around here with the engineering office at the POCO. Trust me i have tried. Thanks for your info.

#26102 05/31/03 11:19 PM
Joined: Oct 2000
Posts: 2,723
Likes: 1
Broom Pusher and
Member
One Electrode system of sufficient size per the largest service entrance conductor should be fine.
Bond each service section to this electrode system via an appropriately sized grounding electrode conductor - according to the size of the service feeder going to that section's KWH meter clip.

How does this sound to everyone??? Should I elaborate more???

Scott


Scott " 35 " Thompson
Just Say NO To Green Eggs And Ham!
#26103 06/01/03 01:38 PM
Joined: Jan 2002
Posts: 324
A
Member
Thanks Scott.

#26104 06/01/03 03:00 PM
Joined: Apr 2002
Posts: 2,527
B
Moderator
arseegee — One reason for individual utility service laterals is to limit fault current at the service entrance.

[There may be supporting discussion in one of the 1980’s NEC preprints about it.]


Link Copied to Clipboard
Powered by UBB.threads™ PHP Forum Software 7.7.5