Back-Purging Unit: Installation Site And Air Supply Requirements - ABB GAA330-M Operating Instructions Manual

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Back-purging unit: Installation site and air supply requirements

Design of the back-purging unit
Distance to sampling probe
Protection from adverse conditions
Compressed-air supply requirements
GAA330-M EMISSION MONITORING SYSTEM
The back-purging unit consists of a protective cabinet with shut-off valve,
6 bar pressure reduction valve, solenoid valves for back-purging, pressure
regulator and 5 l compressed air receiver for effective pressure pulses also
with lower airflow rate.
The distance between the back-purging unit and the sampling probe must
not exceed 5 m (length of the steel-braided compressed-air hoses = 6 m).
Protect the back-purging unit against
Water spray
•
Contact with chemicals
•
Strong sunlight and heat radiation
•
Strong air currents
•
Heavy dust load
•
Corrosive atmospheres
•
Vibration
•
Dry (dew point < 3 °C), oil- and dust-free
•
max. 6 bar for back-purging
•
approx. 4 bar as control air (required for 2-stage back-purging with type
•
PFE2 filter unit)
required flow rate approx. 100 m
•
CAUTION
If the compressed air is not dry and clean, this will result in damage to the
sample conditioning components (valves, filters, sample gas cooler, sam-
ple gas feed unit) as well as to the gas analyzer.
| OI/GAA330-M-EN REV. C
3 /h