SICK GM901-02, Operating Instructions Manual

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3. Perform manual SPAN test (optional), see "Manual SPAN test (optional)",
page 41 .
4. Enter SPAN value, see "Changing the calibration values", page 64 .
7.10.3 Calibrating the GM901-02 with extended calibration
Prerequisite
Only for devices with corresponding type code and temperature range, see "Device
variants", page 15 .
Adjustment of reference value "SPAN" for high temperatures
Analyzers with extended or high temperature calibration (430 °C) have a single calibra‐
tion curve over the entire operating range. To optimize the accuracy of the analyzer at
higher temperatures, a further calculation is required before entering the zero point or
"SPAN" value.
This additional calculation is necessary to better compensate for the difference
between the calibration of the gas cell at ambient temperature and the operating
temperature of the high temperature process.
The additional calculation is not necessary for measured values below 1600 ppm CO
because the effects of temperature changes are not as pronounced.
Preparatory work
1. Press "cal".
2. Set the default temperature value to the actual ambient temperature, see "Param‐
eter settings for the external temperature sensor PT1000", page 59 .
3. Set "Temperature Input External" to "No", see "Setting the use of an external
temperature sensor", page 60 .
4. Make sure algorithm coefficients C3 to C6 are set to "1". Do not set these values,
see "Setting the use of an external temperature sensor", page 60 .
Contact SICK Service when this is not the case.
5. Set SPAN value to "1" see "Changing the calibration values", page 64 .
Procedure
1. Perform zero adjust, see "Zero adjust", page 40 .
2. Enter the offset correction of the zero point measurement, see "Changing the
calibration values", page 64 .
3. Perform manual SPAN test (optional), see "Manual SPAN test (optional)",
page 41 . Note the SPAN value.
4. Perform calculation for high temperature SPAN value:
°
Use Calculation Table "Span offset calculation for units with extended calibra‐
tion" (available at
www.sick.com/GM901/other downloads/ ).
°
Enter the noted SPAN value and the process temperature in the Calculation
Table.
°
Note the high temperature SPAN value.
5. Enter the high temperature SPAN value, see "Changing the calibration values",
page 64 .
6. Reset temperature parameters to reflect process conditions, see "Parameter set‐
tings for the external temperature sensor PT1000", page 59 .
7.11 Zero adjust
CAUTION
A zero point check or adjustment must be carried out before every initial and new
commissioning.
7
COMMISSIONING
40 O P E R A T I N G I N S T R U C T I O N S | GM901-02 8008932/16YT/V4-0/2022-02 | SICK
Subject to change without notice