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Model 979 Series Helium Mass Spectrometer Leak Detector
DRAFT 9/15/03
B-5
Table B-1 lists inquiries that are used to determine internal operating parameters.
All inquiries, except VER, begin with
?
and end with <CR>.
Table B-1
Internal Operating Parameters
Inquiry
Response
?ALL
Nine lines. Each begins with a <cr><lf>. The first line reports the filament bias
voltage. The second line reports the ion chamber voltage. The third line reports
the variable focus voltage. The fourth line reports the repeller voltage. The fifth
line reports the fixed focus voltage. The sixth line reports the suppressor
voltage. The seventh line reports the emission current. The eighth line reports
the value of the offset variable. The ninth line reports the gain value.
?AZ<0
Reports the status of the Auto-zero < 0 function. Enabled or Disabled.
?BACKGROUND
Reports the value of the helium background.
?CALOK
Reports the status of the last calibration.
?CL-XFER
Reports the currently stored contra-flow mode crossover pressure.
?EMISSIONCURRENT
Reports the emission current.
?EXPONENT
A two-character (minus followed by one digit) number indicating the
current manual-mode exponent. The exponent is within the least sensitive range
(as reported by ?RANGE) and the three lower (more negative exponent)
ranges. See also INIT-EXPONENT.
?EXTLEAK
Reports the currently stored value of the external standard leak.
?FILAMENTBIAS
Reports the filament bias voltage.
?FIXEDFOCUS
Reports the fixed focus voltage.
?GAIN
A three-character number consisting of a two-digit gain factor with a
decimal point after the first digit. This inquiry is used for reporting the value of
the gain.
?GL-XFER
Reports the currently stored gross leak crossover pressure.
?INTEXT
Indicates which leak, INTERNAL or EXTERNAL has been selected for use
during calibration.
?IONCHAMBER
Reports the ion chamber voltage.
?LEAK
A six-character number consisting of a two-digit leak rate mantissa with decimal
point after the first digit followed by E
−
then a single digit, which is the leak rate
range exponent (e.g., 1.3E
−
4).
?LPV
Reports the current Leak Rate, Pressures and Valve state.
?OFFSET
A number representing the offset value as a percent of full scale. 50 represents
mid-scale.
Summary of Contents for 979 Series
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