FLK Gas Sampling System - MPIP - Free

SQ250 FLK Gas Sampling System
• Signals to the heat exchanger unit
• Before the motor protective switch in the control cabinet for the heat exchanger unit is switched on, the
control signals must be checked by operating the separate contactors.
• After switching in the main switch on the left side of the control cabinet and closing the protective switch, the
direction of rotation of the blower and the circulation pump can be checked by momentary pressing the
corresponding contactor relays.
Note:
See also the operating manual for the heat exchanger unit, Chapter Start-up.
After termination of the signal test, the sealing check test and the flow check of the measuring gas line should take place. To
do this, a method of changing certain counter values has been provided in the PLC program. See the Chapter Servicing, flow
and sealing tests.
3.2.2 Compressed air
After the check of the compressed air hose and the retraction device with the probe installed, the compressed air can be fed
with the shut-off valves closed.
When using the retraction device with emergency retraction by a compressed air motor, the direction of rotation of the
compressed air motor must be checked by slowly opening the main shut-off valve on the valve combination. When no
voltage is applied, the traverse carriage must withdraw from the kiln. The compressed air motor is stopped in the withdrawn
state by the compressed air limit switch.
The compressed air connections should be tight to minimize consumption.
Note:
For the limit switch settings and the start-up of the traverse carriage see the operating manual for the
retraction device and the valve combination.
3.2.3 Purging process
The purging is started by:
1. The "Start" push-button on the valve combination or in the controller (when the probe is withdrawn only with the
automatic switch in "Manual");
2. When the probe is inserted;
3. Automatically after expiry of the waiting interval between two purgings ( CTR 1 or 2 );
4. The negative pressure in the measuring gas line is too high.
The purging process with compressed air can be checked by pressing the "Start" button on the valve combination.
Once the purging has started, the four-way ball valve is set to the "CLOSED" position. Then the release of the cleaning cycle
(compressed air cleaning) occurs. When finished, the four-way ball valve moves to the position "Blow out condensate". Then
the collected condensate is blown out of the condensate vessels. After this period has expired the four-way ball valve moves
through the "Test" position (pressure balancing of the measuring gas line) into the "Measure" position. Then a low pressure
test occurs after the measuring gas pump has started. When this has terminated, the purging process finishes after a
measurement bridging period.
The purging can be terminated at any time with the "Stop" buttons on the valve combination and in the controller.
With the cleaning cycle, special attention must be paid to the correct sequence for controlling the compressed air valves.
Copyright ® SIEMENS Page 18 04/04