Remote Operation Model GFC7001E Carbon Dioxide Analyzer
Teledyne Analytical Instruments 182

8.6.7. SETTING HESSEN PROTOCOL STATUS FLAGS

Teledyne’s implementation of Hessen protocols includes a set of status bits that the instrument includes in

responses to inform the host computer of its condition. Each bit can be assigned to one operational and warning

message flag. The default settings for these bit/flags are:

Table 8-8: Default Hessen Status Flag Assignments

STATUS FLAG NAME DEFAULT BIT

ASSIGNMENT

WARNING FLAGS

SAMPLE FLOW WARNING 0001
BENCH TEMP WARNING 0002
SOURCE WARNING 0004
BOX TEMP WARNING 0008
WHEEL TEMP WARNING 0010
SAMPLE TEMP WARN 0020
SAMPLE PRESS WARN 0040
INVALID CONC
(The Instrument’s Front Panel Display Will Show The
Concentration As “Warnings”)
0080

OPERATIONAL FLAGS1

Instrument OFF 0100
In MANUAL Calibration Mode 0200
In ZERO Calibration Mode4 0400
In O2 Calibration Mode (if O2 sensor installed )2,4 0400
In CO2 Calibration Mode (if CO2 sensor installed )2,4 0400
In SPAN Calibration Mode 0800
UNITS OF MEASURE FLAGS
UGM 0000
MGM 2000
PPB 4000
PPM 6000
SPARE/UNUSED BITS 1000, 8000

UNASSIGNED FLAGS (0000)

AZERO WARN2 DCPS WARNING
CANNOT DYN SPAN2 REAR BOARD NOT DET
CANNOT DYN ZERO3 SYNC WARNING1
CONC ALARM 13 SYSTEM RESET1
CONC ALARM 23
1 These status flags are standard for all instruments and should probably not be
modified.
2 Only applicable if the optional internal span gas generator is installed.
3 Only applicable if the analyzer is equipped with an alarm options.
3 It is possible to assign more than one flag to the same Hessen status bit. This
allows the grouping of similar flags, such as all temperature warnings, under the
same status bit.
Be careful not to assign conflicting flags to the same bit as each status bit will be
triggered if any of the assigned flags is active.