Test running The unit is normally adjusted to a nominal pressure. The pressure can be changed by adjusting the vacuum relief valve. Please note that it cannot be exceed the max pressure for the unit. For the 7.5 kW DC 11-Module the pressure can be adjusted over the stated max pressure 19 kPa, up to 23 kPa, under the condition that the highest rpm, level 3 (70 Hz) is blocked.
from the impeller blades. As the pump draws cooling air through the vacuum relief valve a weak hissing should be heard. Check the rotation direction of the pump. 5. Measure the pressure. Compare with the dimension point. The pressure can be adjusted by adjustment of the vacuum relief valve, see page 27.
1. Verify that the power is locked out.
3. Connect a manometer for the negative pressure calibrated to –50 kPa to the suction side as close to the pump as possible. 4. Power up the pump and listen carefully for the following sounds: A high-pitched whine is normal
7. It is normal that the pump gets hot during operation 8. When the fi lter is being cleaned, a number of powerful air pulses should be heard over a four minute period with approx. 20 seconds interval
Test running DC Green System Constant speed: The pressure can be adjusted by adjusting the vacuum relief valve, see Service
2.
The system should then run up and adjust itself to the working pressure.
3.
Un-plug the suction equipment.
4.
The system should then after about one minut run down to the saving mode.
To check the regulating function: 1.
All outlets must be shut down. Connect the suction equipment which has the smallest dimension/longest hose.
Service Service points 1. 2. 3. 4.
Lubrication of lower bearing P and S models (always) Lubrication and review of vacuum valve (always) (not fitted to S models) Filter change (fine filter, always) Micro filter (optional)
Constant speed: 2a. Lubrication and review of vacuum valve (always) (not fitted to S models)
DC Green System: 2b. Checking the sensors 3. Filter change (fine filter, always) 4. Micro filter (optional)
DC 11-Module - 37
Part No 94153-C
ENGLISH
2. Check that no persons can be injured if the pump starts and that all outlets are closed.
6. Check the function and tightness of the connected exhaust system.