Start-Up And Operation; Preparation; Setting Up Test Gases; Autocal System With Restrictors - ABB Endura AZ25 Series User Manual

Endura AZ25 series probe
Combustion oxygen monitor

5 Start-up and operation

5.1 Preparation

1. If the probe is not connected permanently to test gas
pipework for automatic calibration purposes, ensure
blanking plugs are securely fitted to the test gas inlet
connections on the probe.
2. If the probe is connected permanently to test gas
pipework for automatic calibration purposes, ensure that
the valve installed in the pipework adjacent to the test gas
connection is closed.
Caution. If the test gas connection is not sealed
when not in use, air leaking into the probe via the
connection causes
pressurized flue, gases venting to atmosphere
through the connection cause corrosion of, and / or
block, the test gas tube. In a negative pressure flue,
air leakage causes high O
3. Check the connections on both the probe and the
transmitter.
Test gas connections must be checked for leak-tight
joints. Leaks, especially on permanently pressurized
AutoCal-fitted probes, can cause errors and drain away
expensive bottles of test gas.
4. Adjust the reference air flow to a stable flow rate between
0.3 and 0.5 l / min (0.64 and 1.06 scfh) for probes without
restrictors or 1 bar (15 psi) for probes with restrictors.
– refer to Section 3.5.5 and 3.5.6, page 13 for probes
fitted with AutoCal.
– refer to Section 3.5.7, page 14 for probes without
AutoCal.
Note. Only perform a final system calibration after the
probe has been thermally stable for 2 hours.
OI/AZ25P–EN Rev. E
measurement errors. In
reading errors.
2

5.2 Setting up test gases

This section prepares the system for manual and automatic
calibration routines by setting up the test gas flows and
pressures to suit different AutoCal / restrictor configurations:

the required test gas flow is 1 l/min (2.118 scfh) for all
configurations

refer to Section 3.5, page 9 for test gas and reference air
supply configurations
Note. The following sections assume the transmitter is
energized and the probe at working temperature (above
a
600 °C), the reference air supply is on and test gases are
available.

5.2.1 AutoCal System with restrictors

To set up an AutoCal system with restrictors:
1. Make test gas and reference air connections as detailed in
Section 3.5.5, page 12.
2. Turn on Test Gas 1 and set the pressure to a nominal
1 bar (15 psi).
3. At the transmitter, check the Calibrate / AutoCal Hardware
/ Hardware Type parameter is set to Internal.
4. At the transmitter, open the Test Gas 1 valve by selecting:
Calibrate / AutoCal Hardware / Valve Manual Control /
Test Gas 1 and pressing
A small icon is displayed to indicate the valve is in the
Open position:
Valve icon
Open position
5. Fine tune Test Gas 1 pressure to 1 bar (15 psi) – this
ensures the correct flow through the restrictors.
6. Turn gas off at the transmitter by pressing
Test Gas 1 off at the supply.
7. Repeat steps 2 to 6 for Test Gas 2 (if present).
8. Refer to IM/AZ20E-EN to perform a calibration when
required.
5 Start-up and operation
to open the valve
.
Valve icon
Closed position
, then turn
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