Instruction manual

NGA 2000 MLT Hardware
INSTALLATION
5 - 8
Emerson Process Management GmbH & Co. OHG
Instruction Manual
90002929
07/2006
5.3.1 Internal Solenoid Valve Block (Option for MLT 1/CAT 200)
For operation with optional solenoid valves, the following indications have to be considered:
Operation with solenoid valves is not possible for 2 - channel analyzer with parallel gas paths.
Supply overpressure for all gases is limited to 50 to 500 hPa when an analyzer is equipped with
an internal solenoid valve block. .
5.3.2 Purge Gas Connections
The analyzers may optionally provide a gas fitting for purging the enclosure (e.g. with nitrogen)
when measuring
❏ low CO
2
concentrations:
N
2
minimizes interference by ambient air
❏ flammable gases:
N
2
gives additional safety in the event of leakage inside the instrument
❏ aggressive components:
purging with air gives additional safety in the event of leakage inside the instrument.
Purge medium must be dry, clean and free of corrosive and solvent
components!
Purging can be accomplished with any inert gas including "instrument quality" air, nitrogen, or
argon which contains no more than trace amounts of a combustible vapor. Compressed air is the
most common and practical purging medium. Bottled nitrogen is uitilized most frequently in
isolated places where no compressed air source is available. Personal protection has to be taken
into consideration in case of N
2
purge in closed rooms, e.g. containers.
Purge gas must be conditioned:
Take care for purge gas temperature: Purge gas should have the same temperature
as ambient temperature of the analyzer but NOT below 20 °C and above 35 °C!
Otherwise it must be cooled or warmed up before let in into the instrument!
Purge gas should be instrumental / synthetic air (free of oil, no corrosive, toxic
or flammable gas componets) or nitrogen depending on application.
GAS CONNECTIONS