Housing Purge - ABB Advance Optima magnos206 Operator's Manual

Housing Purge

When should the
housing be purged?
Housing Design
Housing Purge
Central Unit
Housing Purge
Purge Gas Supply
Requirements
3-12
A housing purge is required if the sample gas contains combustible, corrosive or
toxic components.
A housing purge is possible if the system housing is designed for IP54 (with
connection box) or IP65 (without power supply) protection. The purge gas
connection ports (1/8-NPT internal threads) are factory installed per order.
In gas analyzers with the Caldos25, Caldos27, Magnos206 and Magnos27
analyzer modules there is a gas-tight separation between the central unit and
analyzer. Therefore, the central unit and analyzer can be purged separately
(parallel) or jointly (series).
In gas analyzers with the Limas11 and Uras26 analyzer modules there is no gas-
tight separation of the central unit and analyzer. Therefore, they can only be
purged together. If the central unit and analyzer must be purged separately, the
analyzer module must be installed in a separate IP-54 system housing.
Due to differing purge gas supply requirements, the Limas11, Uras26, Caldos25,
Caldos27, Magnos206 and Magnos27 analyzer modules should not be purged in
series with the MultiFID14 analyzer module.
CAUTION!
For joint purging of the analyzer and central unit, the purge gas must first be
routed through the central unit and then through the analyzer. Flow direction
inversion and leaks in the sample gas path can result in damage to
electronics by corrosive sample gas components.
An analyzer module used to measure corrosive sample gas components
should be the last unit connected in a series.
A central unit with no analyzer module installed can be ordered as a "housing
purge" version. In this case the purge gas connection ports are factory installed in
the terminator plate which installed at the back or bottom of the system housing
instead of an analyzer module.
Nitrogen or instrument air should be used as purge gas (refer to the "Purge Gas
for Housing Purge" section, page 1-6, for detailed information).
CAUTION!
Purge gas can escape from the housing if there are any leak points.
When using nitrogen as the purge gas, take all required precautions against
suffocation.
Purge gas flow must always be restricted ahead of the purge gas inlet!
If the purge gas flow is restricted after the purge gas outlet, the housing
seals are subjected to full purge gas pressure which can result in damage
to the keypad!
Chapter 3: Gas Line Connection 42/24-10 EN Rev. 9