Emerson Process Management GmbH & Co. OHG 7-5
X-STREAM XE
Instruction Manual
HASXEE-IM-HS
10/2010
7
Maintenance & Procedures
7.4 Calibration Procedures
7.4 Calibration Procedures
Note!
To achieve best and proper measuring re-
sults, it is recommended to perform zero and
span calibrations on a regular weekly basis.
Also a zero calibration must always precede
a span calibration!
Zero calibration
To perform a zero calibration supply either
nitrogen (N
2
) or another suitable zero gas
[conditioned ambient air or industrial air (NOT
for oxygen measurement!)] to the gas path.
Span calibration
Supply span gases with concentrations of
80 % to 110 % of the upper measuring range
limit to the gas path. Using lower concentra-
tions may decrease accuracy when measu-
ring above the span gas concentration!
If the oxygen concentration is known, ambient
air may be used for an oxygen channel span
calibration.
X-STREAM gas analyzers support several
calibration procedures:
Manual calibration
Typically a calibration procedure is carried out
manually by supplying the gases sequentially
by hand and activating the procedures via
front panel keys.The operator has to take
care to consider purge times and supply the
proper gases in correct order.
It is the operators responsibility to not perform
a span calibration without a preceding zero
calibration!
Advanced calibration
Advanced calibration is a more comfortable
variation of manual calibration, providing ONE
KEY calibrations supported by internal and/or
external valves. The analyzer automatically
supplies the right gas and considers purge
times.
Remote calibration
Remote calibrations may be activated by
means of digital inputs or Modbus commands.
Calibrations activated via digital inputs re-
quire either internal or external valves to be
installed. Modbus supports both calibrations
with or without valves as well as calibration
sequences.
Unattended automatic calibration
Unattended automatic calibrations are activa-
ted utilizing the analyzer software time interval
setting:
After a specied time interval has elapsed,
the analyzer automatically carries out valve
supported zero or span calibrations.
The main advantage is that no user interaction
is required to start a calibration or during cali-
brations: The analyzer automatically supplies
the right gas, considers purge times and, that
a span calibration has to be preceded by a
zero calibration.
Conguring and performing ca-
librations is important to ensure
proper analyzer function. For
this reason, several calibration
related SETUP and CONTROL
menus and their submenus can
be protected by different access
codes.
In the following sections this
manual does not note when to
enter access codes.
For information about which
calibration related menus can
be access code protected
Chapter 6 - CONTROL menus,
6-5 and SETUP menus, 6-21.
