In this case we are using a compact ejector with integrated valve technology. In other cases we need solenoid valves to switch the function “Vacuum on/off”. They are usually used when pumps or blowers are used as vacuum generators.
The selection of the valves is based on the following criteria:
- Suction rate of vacuum generator
- Control voltage
- Operating principle of the valve (NO/NC)
The nominal flow of the solenoid valve may not be less than the suction ratio of the vacuum generator.
Calculation of the nominal size of the valve
VV = VVE
VV = Nominal flow of valve [m3/h, l/min]
VVE = Existing suction rate of vacuum generator[m3/h, l/min]
Example: VV = 140 l/min = 7 m3/h
For this example we choose:
The used compact ejector of type SCPi 20 is equipped with solenoid valves which eliminates the need for separate valves. A solenoid valve of type EMV-10 with a nominal flow of 20 m3/h would also be sufficient for the function “Suction ON/OFF”.