Teledyne Calibration of the GFC 7001E/EM’S Electronic Subsystems, Dark Calibration Test

Calibration Procedures Model GFC7001E Carbon Dioxide Analyzer

9.6.CALIBRATION OF THE GFC 7001E/EM’S ELECTRONIC SUBSYSTEMS

9.6.1.DARK CALIBRATION TEST

The dark calibration test interrupts the signal path between the IR photo-detector and the remainder of the sync/demod board circuitry. This allows the instrument to compensate for any voltage levels inherent in the sync/demod circuitry that might effect the calculation of CO concentration.

Performing this calibration returns two offset voltages, one for CO MEAS and one for CO REF that are automatically added to the CPU’s calculation routine. The two offset voltages from the last calibration procedure may be reviewed by the user via the front panel display.

To activate the dark calibration procedure or review the results of a previous calibration, press:

SAMPLE		RANGE=50.0 PPM		CO= XX.XX
<TST	TST>	CAL			SETUP
SETUP X.X		PRIMARY SETUP MENU
CFG	DAS RNGE PASS CLK MORE				EXIT
SETUP X.X		SECONDARY SETUP MENU
COMM	VARS	DIAG			EXIT
	SETUP X.X ENTER PASSWORD
8	1	8		ENTR	EXIT
DIAG			SIGNAL I/O
PREV	NEXT			ENTR	EXIT

Offset for CO REF signal

Continue pressing NEXT until ...

DIAG OPTIC		DARK CALIBRATION
PREV	NEXT		ENTR EXIT
DIAG DARK		CO DARK CALIBRATION
VIEW	CAL			EXIT

Calibration runs automatically

DIAG DARK	REF DARK OFFSET: 0.0mV
		EXIT
Offset for CO MEAS signal
DIAG DARK	MEAS DARK OFFSET: 0.0mV
		EXIT

DIAG DARK	DARK CAL 1% COMPLETE
		EXIT
DIAG DARK	DARK CALIBRATION ABORTED
		EXIT

Teledyne Analytical Instruments 205