10
3GZF500725-144 EN 03-2023 | ABB IEC LV MOTORS
For some cases a higher input temperature can be allowed when requested and checked by
the manufacturer.
The outlet water temperature rise is from 5–10 K.
The minimum pressure and amount of cooling water for the basic construction of a water-
cooled motor is shown in the following table. Please check the requirements for pressure and
the amount of cooling water in the case of special constructions.
If the amount of water varies, its temperature rise will be inversely proportional to the flow
rate.
Frame type
Number of
inlets
Cooling water
flow rate
(l/min)
Water pres-
sure min .
(bar)
Water temp .
rise (K)
Heat transfer of thermal
loss in (approx .) ratio
air/water at room temper-
ature (20°C)
Temperature of inlet cool-
ing water
Water-space of st .
frame (l)
25 °C
40 °C
250 KH_
1
26
2
5-10
10/90
30/70
3.8
250 SM_
9.2.
Filling or draining cooling water
When filling, open the air vent plug on top of the motor (see figure 2). Let the cooling water
flow into the motor until it comes out of the air gap. Close the air gap with a plug and seal
the joint with sealing tape or strip. Filling must be done carefully so that no air is left in the
motor’s cooling channels. Check for possible leaks after the piping and joints have been con-
nected.
Emptying can be done with pressurized air. After emptying, the plugs must be re-fitted, and
the seals of the joints must be checked.
10.
Consendation drain holes
It is of special importance with water cooled motors that the condensation drain holes are lo-
cated in the correct position (fig. 1). Check that the condensation drain holes face down-
wards, especially when the mounting arrangement differs from standard.
11.
Water leakage detector
This motor is equipped with float type leakage detector in non-drive end (see figure 2 and 3).
The leakage detector has a magnetic float switch. The magnetic float switch is positioned on
a non-magnetic guide tube. When a specified water level is reached, the magnetic field pro-
duced by the magnet in the float actuates a reed switch (sealed contact) inside the guide
tube.
This closes the electric circuit that transmits the alarm signal to the control board.
