LI-COR LI7200RS, Instruction Manual

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Section 7. Software Reference
Diagnostic Value
The cell diagnostic value is a 2 byte unsigned integer (value between 0 and 8191)
with the following bit map:
bit 15 bit 14 bit 13 bit 12 bit 11 bit 10 bit 9 bit 8
Unused Unused Unused Head detect Toutlet Tinlet Aux_
input ∆Pressure
1=LI-
7200/RS 1=ok 1=ok 1=ok 1=ok
bit 7 bit 6 bit 5 bit 4 bit 3 bit 2 bit 1 bit 0
Chopper Detector PLL Sync <------ (Signal Strength / 6.67) -------->
1=ok 1=ok 1=ok 1=ok
Example: a value of 8061 (0001111101111101 in binary) indicates Chopper not ok,
and Signal Strength = 87% (1101 is 13 in binary, times 6.67)
Bit Name Description
0 to 3 Signal Strength Value × 6.67 = Signal Strength.
4 Sync Always set to 1 (OK)
5 PLL Lock bit, indicates that optical wheel is rotating at the
correct rate.
6 Detector 1 = Detector temperature is near setpoint
0 = Detector temperature is not near setpoint
7 Chopper 1 = Chopper wheel temperature is near setpoint
0 = Chopper wheel temperature is not near setpoint
8 Differential pressure
sensor OK Check range: 1 (Good) = 0.1 to 4.9V
0 = Out of range
9 Aux input OK 1 = Internal reference voltages OK.
0 = Internal reference voltages not OK. Analyzer
Interface Unit needs service.
10 Tinlet OK 1 = thermocouple OK
0 = thermocouple open circuit
11 Toutlet OK 1 = thermocouple OK
0 = thermocouple open circuit
12 Head detect Sensor head attached to LI-7550. 1 = LI-7200/RS
13 Unused, always reads 0
14 Unused, always reads 0
15 Unused, always reads 0
7-20 LI-7200RS Enclosed CO₂/H₂O Analyzer