To be checked
See chapter Confirmed?
➤ Oil level monitor connected?
➤ Is the machine firmly anchored to the floor?
➤ Are all access doors closed and latched and all removable panels in
place and secured? (Sound enclosure)
–
1)
depending on machine
Tab. 32 Check list of installation conditions
7.4 Motor protection
The machine should only be operated with a correctly adjusted motor protection device to protect
the motor from overloading.
A motor overload protection switch that is set too high provides no protection. Incorrect setting can
lead to irreparable motor damage.
➤ Set the motor contactor according to the mains voltage.
7.4.1 Motor protection setting by direct online starting
The machine starts directly and is controlled by the user's pressure switch. The pressure switch
switches the machine on and off as necessary to hold pressure within the set limits.
The overload protection cut-out setting can be higher than the rated motor current to prevent
it from being triggered by voltage fluctuations, temperature influences or component toleran‐
ces.
1. Read the rated motor current from the nameplate and calculate the correct protection setting.
2. Check the motor protection setting.
3. Adjust the protection setting, if necessary.
4. Switch the machine on with the user's pressure switch.
The machine is shut down by the motor overload protection switch?
➤ Allow the motor to cool down.
➤ Switch the machine on again.
Further information See chapter 8.
7.4.2 Motor protection setting by star-delta starting
In the star-delta configuration the phase current is fed via the motor overload protection device.
This phase current is 0.58 times the rated motor current (see motor nameplate).
The overload protection device setting can be 10 % higher than the rated phase current to
prevent it from being triggered by voltage fluctuations, temperature influences or component
tolerances.
1. Switch the machine on from the external control unit.
The machine is shut down by the motor overload protection switch?
➤ Contact authorised KAESER SERVICE.
7
Initial Start-up
7.4
Motor protection
No.: 9_5753 24 E
Assembly and operating manual 2-stage piston compressor
EPC-2-G
55
