SICK EuroFID, Operating Instructions Manual

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32 EuroFID · Operating Instructions · 8011094 V2.3 · © SICK AG
Project Planning
3.3.4
Supply of fuel gas
Installations

Check whether H
2
or an H
2
/He mixture should be used as combustion air (refer to the
type plate and labeling of the analyzer unit; specifications → P. 195, §16.6.2 ).

Ensure a continuous supply of this fuel gas at the “Fuel gas” gas connection.
Recommendation:

Fit a pressure monitor on the fuel gas cylinder which monitors the cylinder pressure and
emits a signal at a certain residual pressure (e.g. 10 bar).

Connect the electrical warning signal of the pressure monitor (if available) to the “Gas
supply malfunction” control input (
→ P. 65, §6.3.6 ).
Explosion protection
Recommendations for explosion protection:

Install a volume flow limiter in the fuel gas supply line.

Install a leakage monitoring device on the fuel gas monitoring device which emits a
signal when H
2
is discharged.

If available, connect the electrical warning signal of the leakage monitoring device (if
fitted) to the “Gas supply malfunction” control input (
→ P. 65, §6.3.6 ).
3.4
Exhaust gas connections
3.4.1
“Exhaust” gas connection
The exhaust gas of the FID measuring system is discharged through the “Exhaust” gas
connection.
Important: The exhaust gas contains steam (consequences

§3.4.3 ).
3.4.2
“Bypass” gas connection
Only applies to the analyzer unit types “wall housing” and “19" slide-in enclosure”.
The excess gas of the ejector pump is discharged through the “Bypass” gas connection: A
mixture of sample gas and instrument air.
If two compressed gas cylinders are provided, an empty compressed gas
cylinder can be replaced without interrupting measurement.
Recommendation:

Instead of a single compressed gas cylinder for fuel gas, install two
compressed gas cylinders.

Install an automatic (pressure controlled) switchover feature for the gas
cylinders.
WARNING: Hazard by explosive substances/mixtures
H
2
can form an explosive gas mixture with air. For this reason a leak in the fuel
gas pipe constitutes a potentially fatal danger.

Implement safety precautions for explosion protection.
NOTICE:
On the analyzer unit types “inline” and “industrial housing”, the bypass gas
flow is discharged from the surrounding tube of the sampling probe.

Pay attention to the installation notes ( → P. 43, §4.3.2 ).