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
- Basic trouble-shooting guide (if not already included in the ops manual)
General
The equipment shall be compliant with the following wrt operation:
- Rated installation voltage of 690Vac.
- Starter shall be typically for minimum 6 starts per hour (subject to
application type and kW rating)
- For units used in continuous running with fewer starts, a bypass contactor
recommended by the soft starter manufacturer shall be used to minimize
heat loss.
- Actuation of bypass contractor shall be achieved by using relay output on
completion of ramp up.
- Operating temperature shall be 0oC to 50oC with adequate derating where
required (application dependent). Also, the equipment shall be suitable for
normal operation without derating, within an altitude range of 0-1000
meters.
2.15 ELECTROMECHANIC MOTOR STARTERS
Where these starters do not fall under the electrical sub-contractor’s scope of
work, the specifications may be used for all co-ordination works.
A. Provide motor starters of electromagnetic, air break type suitable for 3
phase, 50 Hz., 415V, AC System and in accordance with IEC 947-4
B. Starters shall be of the plug-in type mounted on withdrawable trays
including power and control plug pins and earthing contact with facilities
for padlocking.
C. Starters controlling motor less than 11 KW may be of the direct on line
type. For motors of 11 KW and higher ratings employ automatic star delta
starters. Starters shall be provided with three phase overload relays having
thermal characteristics suitable for the associated motor and its starting
characteristics and suitably compensated for ambient air temperature
variation. In addition, provide single phasing protection. Means should
also be inherent in the starter for automatically disconnecting the motor
from the electricity supply in the event of interrupted supply or under
voltage. Provide earth leakage protection for all motors.