Varian 948, Operation And Service Manual

Page: 149 / 176

Models 947, 948 and 960 Leak Detectors Operations and Service Manual
C-5
Table C-2 lists the commands used to set NON-VOLATILE operating parameters. The
current value of the operating parameter is changed to a new value. If parallel enable is
asserted, the response is
cant <CR> <LF>
.
Table C-2 Non-volatile Operating Parameters
Command Response
INIT-2LOG No parameter. The analog leak rate output voltage becomes logarithmic at
2 V per decade.
INIT-3LOG No parameter. The analog leak rate output voltage becomes logarithmic at
3 V per decade.
INIT-AZ<0 Preceded by a single digit, either 0 to turn AUTOZERO off, or 1 to turn the
feature on.
INIT-DAC Sets a positive offset voltage in millivolts to electrically null the analog output
voltage. A number in the range 0 to 255, followed by a space, then INIT-DAC.
INIT-EMISSION Sets the emission current of the ion source. A four-digit number of microamps,
in the range 300 to 2000.
INIT-FILAMENT Sets the operating filament in the ion source. Enter the number of the desired
filament (1 or 2), then a space, then INIT-FILAMENT. For example, entering
1 INIT-FILAMENT<CR> makes Filament #1 in the Ion Source the active
filament.
INIT-FL-XFER Sets the minimum pressure in Torr that must be attained to transfer from gross
leak to fine leak test. A seven-character string, two mantissa digits with a
decimal point between them, E, and a three-character signed exponent
(e.g. 5.0E-02).
INIT-FOCUS Sets the variable focus voltage of the ion source. A three-digit number of volts,
in the range 100 to 250.
INIT-GAIN Sets the gain used for adjusting the helium signal to match a calibrated standard
leak. A two-digit number with a decimal point after the first digit, in the range 1.0
to 9.0.
INIT-GL-XFER Sets the minimum pressure in Torr that must be attained to transfer from
roughing to gross leak test. A seven-character string, two mantissa digits with a
decimal point between them, E, and a three-character signed exponent
(e.g. 8.0E-01).
INIT-ION Sets the ion voltage of the ion source. A three-digit number of volts, in the range
150 to 350.
INIT-LINEAR No parameter. The analog leak rate output voltage assumes the LINEAR mode.
INIT-nREJECT The helium leak rate number in atm cc/sec. The format is: a two-digit leak rate
mantissa with a decimal point after the first digit, followed by E
−
, and then by a
single digit which is the leak rate range exponent.
Use to set the value of reject set point, where n is the set point 1 through 4.
Values outside the working range of the leak detector are not stored.