Specifications

NAIROBI OPERATIONAL HUB
UNOPS Building, UN Lane, Off UN Avenue Tel: [phone]
P.O Box 783,Village Market, 00621 E-mail: [e-mail]
Nairobi, Kenya Website: www.unops.org
UNOPS is ISO 9001 certified
PART 2 PRODUCTS
2.01 GENERAL
A. All the materials required for Grounding system shall be furnished new and
undamaged in accordance with the requirement stated in this section.
B. Conduct soil electrical resistively tests at four locations (minimum) advised
by the Engineer. The Grounding calculations based on the test results shall be
submitted for Engineers approval, to demonstrate that the proposed design of
Grounding system complies with the specifications and standards.
C. For High voltage equipment in Transformer room, a connection shall be
provided from the main Grounding loop. Also Grounding pits shall be installed as
per Local Electric Supplier requirements, which will be isolated from the main
Grounding loop.
D. For communication room, separate Grounding pits shall be installed as per
Local Telephone Supplier requirements, which will be isolated from the main
Grounding loop.
2.02 Grounding connection bar
A. For connection of MV and LV equipment, sub-station shall have high
conductivity copper, Grounding connection bar with minimum dimensions of 50 x 6
mm and mounted on porcelain insulators. The bar shall be of suitable length with
pre-drilled holes at a minimum distance of 50 mm between hole centres.
B. Grounding connection bars for transformer neutral and LV switchboard
frame shall be separate from Grounding bar for HV and transformer frame.
C. Each Grounding connection bar shall have a permanent label to identify the
connections together with the wording "Main Grounding Bar".