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Additional Installation, Operating and Maintenance Instructions (Translation)
English
Edition 07.2010 VEM-Ident-No. 73753 01en
5
Water feeding, technical requirements for the cooling water
The cooling water must have the quality of drinking water. The maximum water pressure is 3.5 bar, and the
maximum temperature of the entering water must not exceed 35 °C. The following minimum requirements for
the cooling system have to be observed.
Size
Flow rate of
cooling water
Min. water
pressure
Temperature rise
of cooling water
[l/min]
[bar]
[°C]
225
10
0,5
6
250
16
0,7
7
280
18
1,0
9
315
18
1,5
8
355
20
2,0
10
The water inlet and outlet are situated on N-side of the housing. Use suitable sealants for the joints.
Size 225 to 280
Size 315/355
The water supply must be secured during operation of the motor.
Operation without cooling water is not admissible.
In addition there is an air relief plug with 3/8 ” thread on N-end of the motor and a water drain plug with 3/8 “
thread at the lowest point for motors of size 225 to 280. When the cooling system is filled, the air relief plug
must be opened. The motor must be filled with cooling water, until the water exits from the air relief hole. The
filling procedure must be done carefully to make sure that no air remains inside the cooling circuit. Then the
air relief hole must be closed. Again an appropriate sealant must be used. Check that the joints are water-
proof.
To empty the motor, take off the plugs for air relief and water drain. After complete drainage the plugs must
be tightened again. If the cooling system is filled again, check that all plugs are water-proof.
Auxiliary devices
Additional thermal motor protection
For monitoring the stator winding temperature it is possible to have thermo couples installed in the motor
(PTC thermistors, KTY or PT100). For their connection suitable auxiliary clamps for auxiliary circuits are
available in the main terminal box or in additional terminal boxes. The connection is done according to the
attached connection diagram.
Anti-condensation heating
The heating power and the input supply voltage are indicated on the name plate of the motor. For their con-
nection either in the main terminal box or in the auxiliary terminal boxes suitable clamps for auxiliary circuits
are provided. The connection is done according to the attached connection diagram. The anti-condensation
heating has to be switched on only after disconnection of the motor. It shall not be switched on while the
motor is in operation.