Buhler GAS 222.21 Ex2, Installation And Operation Instructions Manual

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GAS 222.21 Ex2
6.2.2 Automatic Blowback (External Blowback Control)
For automatic blowback, the shut-off valve in the probe with must have a pneumatic control (optional). The control unit for the
system is designed for sequential valve control, i.e.:
1. Close the shut-off valve in the probe using the pneumatic control.
2. Open the solenoid valve between the pressure vessel and probe for approx. 10 seconds.
3. Open the shut-off valve in the probe.
Blowback can also be set as a closed process at intervals ranging from several minutes to hours or even days based on require-
ments.
6.3 Maintenance Schedule
NOTICE
When using the probe in explosive areas the maintenance schedule must be observed!
Maintenance schedule for normal ambient conditions:
Component Interval in operating
hours Work to be performed To be performed by
Entire probe every 8000 h – Check gas connections
– Check safety devices and controllers
– Check electrical protective measures
– Working properly, dirt, visual inspection for dirt/
damage.
If damaged, replace or have repaired by Bühler.
Operator
Ball valves every 8000 h – Check ball valve function and check for leaks. Operator
Filter every 8,000 h – Check dirt level of filter. Operator
Seals every 8,000 h – Replace O-rings.
– Replace seals after every filter change.
Operator
Pressure vessel every 8,000 h – Drain condensate Operator
Drive 1 x per year – Replace seals, guides and lubricants. Manufacturer
Entire probe
With respect to ball valve,
pneumatic and solenoid
valves
after 20,000 h or
3 years – Inspection by Bühler Service technician /
Bühler
Limit switch after 5 years – Replace seals on the shaft and the housing cover. Operator
19 Bühler Technologies GmbH BE460048 ◦ 08/2019