FLK Gas Sampling System - MPIP - Free

SQ250 FLK Gas Sampling System
The purging duration should be kept as short as possible. However, it should be ensured that after purging, the low pressure,
if present, returns to its normal value.
It is therefore practical to match the purging duration and interval to local conditions.
- Setting the purging duration
• In order to prevent initiation of purging due to the expired purging interval time, this time must be temporarily set to a
high value (CTR 1 to 300 minutes for example).
• After approx. -0.08 bar is obtained, the purging process is started.
• Then the low pressure is checked on the pressure gauge.
• If the low pressure is the same as previously, then the purging duration (CTR 3) can be left as it is.
- Setting the purging interval period:
• In order to prevent initiation of purging due to the expired purging interval time, this time must be temporarily set to a
high value (CTR 1 to 300 minutes for example).
• Then it must be found how long it takes on average until the low pressure in the measuring gas line has reached approx.
-0.08 bar. The low pressure can be read on the pressure gauge in the valve combination.
• The time that has passed since the last purging can be read out from the CTR 1 in minutes using the OP3 Operating
Panel.
• The value obtained in minutes can now be entered in the CTR 1.
• The limit contact in the pressure gauge for the release of the purging by low pressure should
be set to -0.15 bar.
If during longer operation an increasingly shorter purging interval period is found, then the low pressure must be checked
directly after purging. If the low pressure does not correspond to the normal value and no fault can be found, the purging
duration in the CTR 3 can be increased to 8 sec.
4.3 Leakage test
This should be carried out every six months or after each manual cleaning of the measuring gas line and after replacement or
repair of various parts in the measuring gas line. ( pump, filter, gas cooler, etc.).
To simplify the low-pressure ( leakage ) test of the complete system a method has been provided in the programmable logic
controller of appropriately controlling the measuring gas four-way ball valve and the measuring gas pump.
Here two procedures must be carried out:
4.3.1. Leakage test between the four-way ball valve and the measuring gas pump
4.3.2. Leakage test of the probe, filter and condensate vessel.
When doing this, it is essential that the first test is correctly concluded and the sealing of the measuring gas connection is
guaranteed.
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