16
4.5C Calibrating the Oxygen and Thermocouple Inputs
Refer also to Fig 4.1C on previous page.
Select the Commissioning Pa.
Automatic Cold Junction Compensation (ACJC) Constant
COMMISSIONING
ACJC const & ENT
➞
➞
Twice
Advance to electrical calibration procedures.
▲
Operate for approximately three seconds to gain access to the electrical
calibration procedures within the Commissioning Page.
Max (O
2
) mV x x x x x x
Min (O
2
) mV x x x x x x
Cell temp zero x x x x x x
N o t e .
'x x x x x x' in the following illustrations is a numerical code used for
software analysis during manufacture and can be disregarded.
OXYGEN INPUT ELECTRICAL CALIBRATION
Connect the millivolt source in place of the 'PROBE CELL' connections – see
Section 5.4.1 or 5.4.2 in ZMT/0011.
Range Maximum
Set 217.6 mV on the millivolt source, i.e. simulating 0.05%O
2
at 1400°C.
Set '217.6' on the upper display.
Store.
Advance to next parameter.
Range Minimum
Set –6.4mV on the millivolt source, i.e. simulating 25%O
2
at 1400°C.
Set '–6.4' on the upper display.
Store.
Advance to next parameter.
Disconnect the millivolt source from the 'PROBE CELL' terminals and remake
original cell connections.
▼
▲
or
Enter
▼
▲
or
Enter
CELL THERMOCOUPLE INPUT ELECTRICAL CALIBRATION
Connect the millivolt source in place of the 'CELL T/C' connections using
Ni-Cr/Ni-Al compensating cable – see Section 5.4.1 or 5.4.2 in ZMT/0011.
Cell Temperature Zero
Measure the ambient temperature at the 'CELL T/C' terminals and, from
standard type K thermocouple tables, obtain the millivolt equivalent of this
temperature (a).
Subtract (a) from 0 and set the resultant value on the signal source.
Example.
Ambient Temperature: 25°C
Millivolt equivalent: 1.00mV
Set millivolt source to: 0 – 1.00(mV)
– 1 . 0 0 m V
Set '0' on the upper display.
▼
▲
or
Continued opposite.