11239449 Installation, operation and maintenance manual – Squirrel cage motor – W Line - Horizontal and vertical l 25
4.6
COOLING
The motor cooling system type may vary according to its
application.
Only the correct installation of the motor and of the cooling
system can ensure its continuous operation without
overheating.
ATTENTION
The protection devices of the cooling system
must be monitored periodically.
The air and/or water inlets and outlets must
not be obstructed, because this could cause
overheating and even lead to the motor
burnout. For further details, refer to the motor
dimensional drawing.
4.6.1
Cooling system characteristics
Figure 4.4: WGM motor cooling
Figure 4.4 legend:
1.
Water inlet
2.
Water outlet
3.
Frame with internal channels for water circulation
On water jacket cooled motors, the internal heat is
dissipated by the water circulating inside the frame.
The water supply system must be installed by the user,
complying with the characteristics specified on the cooling
system nameplate affixed to the 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.
Table 4.7: Cooling system technical characteristics (referential
values)
Frame
Flow
(L/min.)
Maximum
load loss (bar)
Maximum
working
pressure
(bar)
315 35
1
4
355 45
1
4
400 55
1
4
450 80
1
4
500 90
1
4
560 100
1
4
4.6.2
Cooling water characteristics
Make use of treated industrial water with the following
characteristics:
pH: 6.0 to 8.0;
Chlorides: < 40 ppm;
Sulphates: < 50 ppm;
Nitrates: < 10 ppm;
Iron: < 0.2 ppm
Ammonia: < 10 ppm;
Conductance: < 500 μS/cm;
Maximum size of charged particles in the water: ≤ 0.1
mm.
ATTENTION
In an emergency case, the motor can also be
cooled with seawater for up to a maximum of
30 consecutive days; however, that can only
be done twice during the motor useful life.
After the operation with seawater, it is
necessary to clean the cooling circuit with
treated industrial water.
4.6.2.1
Cooling water temperature
Motors cooled by water jacket are able to operate with the
cooling water temperature in the inlet as specified in the
project and indicated on the plate affixed to the motor.
4.6.3
Protection devices
The protective devices of the cooling system must be
monitored periodically as described in the section 4.5 of
this manual.
1
2
3
