Technical data

CHAP-04.10 ELECTRICAL POWER DISTRIBUTION, DRIVES, CONTROL &
ILLUMINATION ELECTRICAL
Page 16 of 50
04.10.06. Design basis for equipments & installations
Ambient conditions of shop units
Generally following ambient temperature will be considered in Electrical /
Control Rooms.
S.N.
Area
Ambient Temp
A.
Electrical Rooms
1.
LT Sub-station/ switchgear room
(Pressurized ventilation)
+ 45 Deg. C
2.
MCC rooms (housing intelligent
MCCs, VFD panels, TR
controllers, RI/Os etc.)
+ 35 Deg. C
3.
Cable basements / tunnels
+ 50 Deg. C
B.
Control Rooms
1.
Control rooms – Air conditioned
+ 24 Deg. C
- Equipment selection and derating will generally be based on ambient
temperature of + 50 Deg.C. For specific areas and shops, the
ambient temperature conditions indicated above will be taken into
consideration and equipment suitably derated wherever necessary.
- Equipment installed in MCC rooms/Control rooms will be designed
for + 50 deg C so that in case of failure of Air-conditioning/ventilation
facilities also the equipment should not be affected.
- The equipment offered should be suitable for smooth, efficient and
trouble free service in the tropical humid climate prevailing at plant
site and under the ambient temperature conditions indicated above
for the different shops and areas. In hot areas of higher temperature
conditions, the equipment will be adequately protected against
damage from radiant heat and hot air.
- The equipment will be designed to give efficient and reliable
performance under heavy steel mill conditions and will be such that
the risks of accidental short-circuit due to animals, rodents and
vermin are obviated.
- The quantities of equipment, cables, cable terminations, straight
through joints, cable supporting structures, earthing / lightning and
erection materials, will be as per actual requirement in accordance
with the approved detail engineering drawings.