PACKAGE : I Bid Document VOLUME : II - Public Health Engineering

Hot thermal withstand curve shall have a margin of at least 10% over the full load
current of the motor to permit relay setting using motor rated capacity.
The motors subject to reverse rotation shall be designed to withstand the stress
encountered when starting the non – energized shaft rotating at 125% rated speed in
reverse direction.
The motors shall be provided with Pt:100 type temp. detector probe at both
D.E & non DE bearings with alarm & trip contacts (4 Nos. + 4 NC) and the leads of
the Embedded temp. detector shall be brought out to a separate terminal box.
The motors of 56.25 Kw & above shall be provided with embedded winding temp.
detector to monitor & trip the motors in case of excess temp.
The motors shall be smooth in operation and the noise level shall not exceed 85 db
at 1.5m from the motor. The vibration level of the pump & motor shall be within the
specified limit of IS : 11724.
The motors above 18.75 KW shall be equipped with built in anti condensation
thermostatically controlled space heater of adequate rating suitable for operation at
220V, AC supply. Separate terminal box for the space heater connection are to be
provided.
The motors shall be provided with antifriction bearing unless sleeve bearings are
required as manufacturing standard. Vertical shaft motors shall be provided with
thrust & guide bearings. The bearing shall be grease lubricated both at DE & NDE
and the same shall be provided with seals to prevent leakage of lubricant or entrance
of foreign matter like dirt, water etc. into the bearing area.
The frame of the motor shall be provided with two separate & district earthing
terminals complete with tapped holes, G. I. bolts & washers for external earthing
with G.I. Flat of size 40 6 mm & above.
The motor terminals box shall be detachable type & located in accordance with IS
clearing in motor base plate foundation. It shall have adequate space inside for
terminating 3 core, 1.1Kv gd upto 95 sq. mm PVC/XLPE Al-conductor cable.
Terminals shall be stud type & thoroughly insulated from frame to provide good
insulation value. The terminals shall be clearly identified with markings. Direction
of rotation shall be marked on the NDE of the motor. The terminal box shall be
capable of withstanding max system fault current for a duration of 3.0 sec.
DTS : Detailed Tender Specification. Page 196