Varian 990 dCLD II, Operation Manual

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Model 990 dCLD II Component Leak Detector
3-14
LOG BAR
GRAPH DISPLAY
LINEAR BAR
GRAPH DISPLAY In LOG BAR GRAPH DISPLAY mode, the 50-segment bar graph
display on the optional front control panel represents the entire
leak rate range of the leak detector, spanning from 10
−
11
atm cc/sec
to 10
0
atm cc/sec. The scale is displayed above the bar graph and
LOG is displayed to the upper right of the bar graph.
In LINEAR BAR GRAPH DISPLAY mode, the 50-segment bar graph
display on the optional front control panel represents the mantissa
value of the leak rate, spanning from 0 to 10. The scale shows
below the bar graph and LIN is displayed to the lower right of the
bar graph. The numerical display, located to the far right of the bar
graph, displays the leak rate exponent value. This mode offers
exceptional resolution within a decade.
Set the display to LOG or LINEAR on the Output Control Set-Up
screen (Section 4.6.5 “Output Control Setup” on page 4-16).
LINEAR ANALOG
OUTPUT
1 V/DEC LOG
OUTPUT ANALOG options allow you to configure the output voltage to the
I/O port (J3) on the back of the control unit. The options for output
are LINEAR and 1, 2, or 3 volts per decade LOGarithmic output.
To set the leak rate analog output to LOG, issue the INIT- n LOG
command, where n is 1, 2, or 3 volts or, if the optional front control
panel is installed, toggle to the desired LOG output value on the Out-
put Control Set-Up screen (Section 4.6.5 “Output Control Setup” on
page 4-16).
To set the leak rate analog output to LINEAR, issue the
INIT-LINEAR<CR> command, if the optional front control panel is
installed, toggle to the LINEAR ANALOG OUTPUT on the Output
Control Set-Up screen (Section 4.6.5 “Output Control Setup” on
page 4-16).