Teledyne BDS-3960 - Oxygen analyzer - Manual (Page 50)

Maintenance BDS 3960
Teledyne Analytical Instruments 50
A zero calibration is not recommended during the first 10 days of
the operation of the cell.
The ZERO button on the Main screen is used to enter the zero
calibration function. Zero calibration can be performed either
automatically or manually.
In the automatic mode, an internal timer will purge sensor for five
minutes before registering the zero offset of the sensor plus electronics.
As the timer counts down, you can force the analyzer to accept the
current zero offset using the Accept button. Pressing the Accept button
anytime during the countdown period forces the analyzer to accept the
zero offset calibration.
Pressing Cancel will return the analyzer back to the analyze mode
without accepting the zero calibration. In this case, the previous zero
calibration values will remain as the current values.
4.4.1.1 Z ERO F AILURE
The analyzer checks the output of the cell at the end of the span. If
the raw output of the cell produces an Analog to Digital converter count
less than 4000 on amplifier gain 0, the zero will not be accepted. The
analyzer will use the previous calibration values, and display at the top
of the main screen:
ZERO-CALIBRATION
ERROR
4.4.2 Span Cal
The SPAN button on the main screen is used to span calibrate the
analyzer. Span calibration can be performed automatically or manually.
In the automatic mode, an internal timer will purge sensor for five
minutes before taking in the zero offset of the sensor plus electronics.
Again, the ACCEPT button can be pressed at anytime during the
countdown period to accept the zero offset calibration.
Pressing the CANCEL button will return the analyzer to the
analyze mode without accepting the zero calibration. The previous zero
calibration will still be in effect.