FLK Gas Sampling System - MPIP - Free

SQ253 Valve Combination
3. Operation
3.1 General information
This equipment unit has been supplied functionally tested. Therefore, no complicated checks of the separately installed
devices are needed.
3.2 Start-up
Warning! The valve combination in conjunction with the withdrawal device must only be put into operation by
qualified personnel, who are familiar with all maintenance measures. Unauthorized operation and improperly carried out
start-up procedures can cause damage.
The start-up is mainly restricted to a check of the wiring, a functional check and a leakage test of the complete measuring
equipment.
3.2.1 Electrical start-up
After checking the wring to the control cabinet, the following functional checks can be carried out. These should be done
before the compressed air is switched on.
• The individual settings on the four-way valve should be selected from the PLC controller using the OP3
Operating Panel.
• Similarly, the function of the compressed air valves -Y2, -Y3, -Y4, and -Y5 should be checked.
• It must also be checked whether the flushing is initiated and started by the local push buttons. The flushing
process must also be started by simulating low pressure (turning back the limit switch contacts to -300 mbar).
• The flushing sequence must be checked according to the sequence in the operating manual for the controller.
3.2.2 Compressed air and leakage test
With the compressed air it must be ensured that the 6...8 bar pressure, the quantity and the quality conform to the
specification.
Caution:
There should be no one situated in the front area of the probe.
The compressed air must be shut off immediately if any leaks occur.
Turn-on should be carried out slowly and special attention must be paid to the joining pieces.
The compressed air part with the valves should be checked for sealing tightness (use leak-seeking spray or soap-water
solution as an aid).
After starting the flushing, the connecting lines to the filter and the probe should be tested for sealing tightness once the leakseeking
agent has been applied.
If a compressed air motor is being used on the withdrawal device, the function of the withdrawal valves must be checked.
• In the unenergized state the solenoid valve (Figure 2, Item 5) must be open and the compressed air motor driven.
• When the pneumatic limit switch on the withdrawal device is operated, the pneumatic valve (Figure 2, Item 4)
closes and shuts off the compressed air feed to the motor.
Note: The solenoid valve must close absolutely tight when energized, because otherwise the traverse carriage will
move slowly in operation.
Copyright ® SIEMENS Page 66 04/04