Operation
5.4 Operating functions
OXYMAT 64
64
Operating Instructions, 06/2008, A5E00880383-03
5.4.3.7
Drift values (function 25)
25 Drift values
O
2
Zeropoint: O.OO vpm
Span MR4: -36.OO vpm
Drift values reset
Figure 5-22 Drift values
This function displays the drift values of all measuring ranges as a total. Every deviation is
added to the existing drift value. This value is deleted when the device is switched off, i.e. all
measuring ranges have 0 as the drift value following a restart.
5.4.3.8
Sensor calibration (function 26)
Note
As soon as a calibration process is triggered by this function, all existing span and zero
settings are deleted. We therefore recommend that you save your current settings using
function 75 'Save user data' before you call function 26.
You can recalibrate the sensor characteristic using this function. This function guarantees
that the displayed O
2
concentration agrees with that of the ambient air.
We recommend that you carry out this function if the calibration tolerance is too large when
calibrating with one of the functions 20 or 21.
Note
Prior to this step you must first check the analyzer for leaks since these can also result in an
excessively large calibration tolerance.
The sensor calibration must then be carried out before calibrating the zero and span
(functions 20 and 21).
The setpoint of the ambient air is 20.64 %; this is an annual average. This takes into account
the fact that moisture displaces O
2
.
The calibration takes place in two steps.
1.
The sensor zero is first adjusted using ambient air.
2.
The span of the sensor signal is then calibrated using a previously defined calibration
gas.