LUDLUM 3030, Manual

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Model 3030 & 3030E Series Technical Manual
Section 7
Ludlum Measurements, Inc. Page 26 November 2017
QC Off/Normal QC/Background Update Only/Manual QC Only
: If enabled,
24 hours after the last QC check, the QC LED turns on and a QC check
must be run before the normal operation can resume. The “Normal QC”
check takes both an alpha and beta source count and a background count.
The “Background Update Only” takes only background counts and replaces
the current background subtract values with the new values. In the
“Background Update Only” mode the display shows the counts in CPM
with one decimal place. Manual mode allows the QC button to start a QC
test but does not automatically require one after 24 hours. Manual QC
option only available with firmware 39013N31 or higher.
If the QC mode is disabled then a QC test cannot be started with the QC
button.
Update Efficiency
: If enabled, the efficiencies calculated during the QC
check will replace the efficiencies used for the DPM calculation. This option
is only available in the Normal QC check mode.
Update Background Subtract
: If enabled, the background readings
received during the QC check will replace the current background subtract
values. This option is only available in the Normal and Background Only
QC check modes.
Override Count Time
: If enabled, the count times set by the count time
switch on the front of the instrument are overridden using the values in the
alpha, beta, and background QC count times.
Last QC Performed
: This is the last date and time a successful QC check
was performed.
Last Alpha/Beta Efficiency
: The last time a QC check was run, this was the
computed efficiency.
Standard Alpha/Beta Efficiency
: These are the values that the QC check
will use to determine pass/fail. If the calculated efficiency is outside the
Standard Efficiency by the Allowable QC Efficiency %, the QC will fail.
Allowable QC Efficiency ± %
: This is the range for how close the computed
efficiency must be to the standard. A standard of 25% with an allowable
range of 5% specifies that to pass the QC check, the efficiency must be in
the range of 20% to 30% to pass.
Source Size
: The DPM value of the source size is saved to the instrument
and is used to determine the efficiency during a QC check.