24 l
Installation, operation and maintenance manual – Squirrel cage motor – WGM20 Line 14108242
4.6
COOLING
Only the correct installation of the motor and of the cooling
system can ensure its continuous operation without
overheating.
4.6.1
Cooling system
The motor water jacket cooling (IC71W) is done by the
axial water flow along to the frame and the cyclically
internal air circulation.
With the motor running, the internal fan causes the air to
circulate internally and to pass through the cooling
channels around the frame, cooling the motor internal
parts.
Figure 4.4: WGM20 motor cooling
Figure 4.4 legend:
1.
Water inlet
2.
Water outlet
3.
Frame with internal channels for water circulation
The water circulating inside the frame dissipates the motor
internal heat.
The user must install the water supply system, complying
with the characteristics specified on the cooling system
nameplate fixed on motor frame.
ATTENTION
In order to ensure proper operation and
prevent overheating of the motor, the data
of the cooling system informed on the
motor cooling system nameplate must be
strictly followed;
The water inlets and outlets must not be
obstructed, because it can cause
overheating or even lead to burning the
motor.
4.6.1.1
Cooling system characteristics
Table 4.7: Cooling system technical characteristics (referential
values)
Motor
Frame
Water
Flow
(l/min.)
Operation
pressure
(bar)
Maximum
system
pressure
(bar)
Maximum
system
losses
(bar)
355
50
4
6
0,7
400
57
4
6
0,7
450
79
4
6
0,7
500
100
4
6
0,7
560
100
4
6
0,7
4.6.1.2
Cooling water characteristics
Make use of treated industrial water with the following
characteristics:
pH: 7.0 to 8.0;
Chlorides: < 50 ppm;
Sulphates: < 50 ppm;
Nitrates: < 10 ppm;
Iron content: < 0.3 ppm
Hardness < 150 ppm
Alkalinity < 200 ppm
Ammonia: < 10 ppm;
Conductivity: < 400 µS/cm;
Maximum size of charged particles in the water: ≤ 0.1
mm.
4.6.1.3
Cooling water temperature
In motors cooled by water jacket, the maximum
temperature difference between the inlet and outlet of
water must not exceed 10°C.
4.6.1.4
Protective devices
ATTENTION
The cooling system protection devices must
be monitored periodically.
The water inlet and outlet must not be
obstructed, because it can cause overheating
or even lead to burning the motor. For more
details, consult the motor DIMENSIONAL
DRAWING.
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2
3
1
2
3
