Pfeiffer Vacuum OKTA 500 ATEX, Руководство по эксплуатации

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6 Operation
6.1 Putting the vacuum pump into operation
Before switching on
1. Check the lubricant levels on both sight glasses.
2. Compare the specifications on the motor rating plate with the available mains voltage and fre-
quency.
3. Make sure that the suction chamber is free from all foreign matters.
4. Check the vacuum pump for visible damage and put the vacuum pump into operation only in a
correct state.
5. Protect the vacuum pump from sucking in contamination using suitable measures (e.g. dust filter).
6. Make sure that the shut-off units on the pressure side open before starting the pump.
6.2 Operation with frequency converter
6.2.1 Observe the voltage slew rate
NOTICE
Damage to motor components when operating with frequency converter
Operation of the motors with standard insulation resistance on a frequency converter may lead to po-
tential damage of the motor insulation from an output voltage of > 480 V.
► Use a suitable filter to smooth voltage peaks as output switching of the frequency converter, e.g.
sinus filter.
► Observe the permissible voltage slew rate.
– SR max (Δu/Δt) =
1.5 kV/μs
► Observe the permissible impulse voltage at the motor terminals.
– V max. = 1.35 kV
Frequency converters generate a pulse width modulated (PWM) motor voltage that comprises voltage
blocks with a relatively steep rise and fall speed. The steepness of the flanks of the voltage blocks de-
fine the voltage slew rate (SR = Δu/Δt). Factors which influence the voltage slew rate are the line length,
line cross-section and shielding. Information is provided by the motor manufacturer in accordance with
IEC60034 and IEC61800-2.
Configuring the frequency converter
► Observe the instructions of the manufacturer regarding installation and operation.
► Observe the maximum permissible torque of the motor.
► Set the current limit according to the rated motor current.
► Observe the permissible speed range of the vacuum pump.
6.2.2 Observe the mechanical resonance
NOTICE
Damage from mechanical resonance when operating with frequency converter
The use of a frequency converter allows operation of the vacuum pump with variable speed ranges.
Potentially critical speed ranges lead to increased frequencies and vibrations. Permanent operation in
critical speed ranges impairs running behavior of the vacuum pump. Damage is caused to the hous-
ing, gear, bearings, seals and motor.
► Decouple the vacuum pump mechanically by means of an anti-vibration buffer on the pump feet.
► Install the compensators at the inlet and outlet flange.
► When installing the vacuum pump, always ensure a new vibration-capable arrangement with
specific structure resonance frequencies.
Operation
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