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
RCCBs shall be available in 2 and 4 pole versions with current ratings
from 16A to 100A and an earth leakage trip rating as specified in the
schedule of points. They shall be suitable for operation on 415V, 3 phase,
4 wire, 50 Hz supply. They shall have an operating temperature from -5 to
+ 60° C. RCCB shall have a trip indication on the front face by a red
mark. It shall be possible to achieve vertical discriminations with RCCBs.
RCCB alone shall have a short circuit withstand capacity of 3 KA. RCCB
must be protected with short circuit protective devices installed upstream
inside the DB enclosure having appropriate fault level protection.
RCCB shall consist of the following mounted in a robust body of all
insulated material:
- A current transformer
- A tripping coil with contact assembly
- Main supply contact
- On/Off switch
- A test button
- A trip free mechanism
Where a RCCB is used a s a separate item and not housed within a
distribution or switchboard, it shall be housed in a dust protected enclosure
to prevent accidental contact with live terminals.
I. Where contactors are shown in DBs, the distribution board shall deemed
to be understood as a multiple section board.
J. All outdoor MCB distribution boards shall be in weatherproof enclosures.
K. The term RCB shall mean an MCB with built-in earth leakage protection
similar to‘Quickguard’ of Square-D
L CONTACORS
The contactors shall conform to BS 775, IEC 947-4 suitable for Class II
duty and having a making and breaking capacity in accordance with
utilization category AC3.
Unless specially required otherwise the operating coil shall be rated for
240V 50Hz.
Contactors shall be rated for continuous duty.
Contactors not forming a part of Distribution Board shall be housed in a
purpose made enclosure having appropriate IP rating suitable to the
mounting location