Commissioning
7.2 Switching on
1LE7 shaft heights 71 ... 315
Operating Instructions, 04/2022, A5E51689275A-AA
77
7.2
Switching on
Measures for start-up
After installation or inspections, the following measures are recommended for normal start-
up of the motors:
•
Start the motor without a load. To do this, close the circuit breaker and do not switch the
motor off prematurely. Switching the motor off again while it is starting up and still
running at slow speed should be kept to a bare minimum, for example for checking the
direction of rotation or for checking in general. Allow the motor to run to a standstill
before switching it back on again.
•
Check mechanical operation for noise or vibration at the bearings or end shields.
•
If the motor is not running smoothly or is emitting abnormal noises, switch it off, and
determine the cause of the fault as it runs down.
•
If mechanical operation improves immediately after the motor is switched off, then the
cause is magnetic or electrical, e.g. voltage imbalance, magnetic imbalance. If mechanical
operation does not improve immediately after switching the motor off, then the cause is
mechanical, e.g. an imbalance in the electrical motors or in the driven machine,
inadequate alignment of the machine set, operation of the motor with the system
resonating (system = motor + base frame + foundations etc.).
•
If the motor runs perfectly in terms of its mechanical operation, switch on any cooling
devices present and continue to monitor the motor for a while as it idles.
•
If it runs perfectly, connect a load. Check that it runs smoothly.
Read off and document the values for voltage, current, and power.
Where possible, read off corresponding values for the driven machine and document
them as well.
•
Monitor the bearing temperature, winding temperature, etc. until the system reaches a
steady state.
Document these, provided this is possible with existing measuring instruments.
NOTICE
Damage of the motor
The motor may get damaged if the vibration values are not strictly complied with.
•
In operation, maintain vibration values in accordance with DIN ISO 10816-3.
