ABB EasyLine EL3000, Operating Instruction

Page: 115 / 216

EL3000
CONTINUOUS GAS ANALYZERS | OI/EL3000-EN REV. D 115
9 Calibration
Calibration control
Manual and automatic calibration
Manual Calibration
Manual calibration is normally controlled on the display and
operation unit of the gas analyzer separately for each sample
component.
Refer to
Manual calibration: execution on page 125.
Automatic calibration
Automatic calibration is usually started cyclically on a time-
controlled basis by the internal clock of the gas analyzer jointly
for all sample components.
• Automatic calibration can also be started by an external
control signal or via the Modbus as well as manually on the
display and operation unit of the gas analyzer.
• Automatic calibration can be blocked by an external control
signal or via the Modbus.
Refer to
Automatic calibration: Control on page 118.
Status signal during calibration
The ‘Function check’ status signal is set during calibration.
For automatic calibration, this is the time period from the gas
switch from sample gas to test gas to maximum 4× the longest
set low-pass time constant (see
Set low-pass time constant on
page 148) plus the purge time after the new gas switch from test
gas to sample gas.
There are two cases distinguished for manual calibration:
• If no valves are configured, the status signal goes out
when leaving the calibration menu.
• If at least one sample gas valve (or a digital output with
valve function) is configured, the status signal goes out
after a maximum of 4× the longest set low pass time
constant plus the purge time after the new gas switch
from test gas to sample gas.
Depending on the configuration of the signal inputs and outputs
(see
Configuring signal inputs and outputs on page 152), the
status signal is issued with the ‘Function check’ function on a
digital output.
Current output signal during calibration
In the configurator, it is possible to set whether the current
signals on the analog outputs
• can follow measurement value changes during calibration.
• are held at the last measured value prior to starting
calibration or
If the current signals are configured to ‘Hold’, the analog outputs
are held until the ‘Function check’ status signal has been cleared.
Limit values during calibration
If limit values are activated, they are also active during
calibration, see
Limit values on page 147.
Limit value monitoring is not active during calibration if the
current signals are configured to ‘Hold’, see
Current output
signal during calibration on page 115.
Plausibility Check during calibration
If during calibration, the gas analyzer finds implausible values
(e.g. if the end-point and zero point values are equal), the
calibration is aborted and the device issues a status message
503 (see
Possible status messages
on page 168).
The values stored for the last calibration remain in effect.