Endress+Hauser 2-Pack TDLAS, Safety Instruction

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2-Pack/3-Pack TDLAS Gas Analyzer XA02751C
Hauser 17
Intermittent Opera -
tion
If the analyzer is to be stored or shut down for a short time period, follow the
instructions for isolating the measurement cell and sample conditioning sys -
tem (SCS).
To isolate the measurement cell for short-term shutdown
The analyzer can be isolated from the primary sample bypass section for
short-term shutdown or maintenance of the analyzer while allowing the
sample bypass flow to continue in a steady-state mode.
1. Close the sample flow meter metering valve (adjustment knob turned
clockwise) for each measurement channel. Do not over tighten the
metering valves or damage could occur.
2. Allow any residual gas to flow out of the measurement cells.
3. Close the low pressure flare or atmospheric vent header shut-off valve
for the effluent from each measurement cell.
To isolate the SCS for short-term shutdown
The sample conditioning system (SCS) can be isolated from the process sam -
ple tap for short-term shutdown or maintenance of the SCS without requiring
the shutdown of the field pressure reducing station.
Due to the high pressure of the process sample, it is advisable
to allow the sample bypass flow to continue during short-
term isolation of the analyzer. Continuing sample bypass flow
allows the field pressure regulator to continue normal
operation without possible overpressure and activation of the
relief valve in the event the pressure regulator leaks when the
downstream flow is discontinued.
Never purge the analyzer with air or nitrogen while the
system is powered up.
If the system will not be out of service for an extended period,
it is advised that power remain applied to the sample
transport line electric tracer, if applicable, and the sample
system enclosure heater.
Process samples may contain hazardous material in
potentially flammable and/or toxic concentrations.
Personnel should have a thorough knowledge and
understanding of the physical properties and safety
precautions for the sample contents before operating the
SCS. For more information →  5.