Chapter 4 Unit Setup
76
h. 8
th
row “Board ID” has board ID number
i. 9
th
and 10
th
rows have data column labels
j. 11
th
row to end has plateau plot data (HV set & read and Gamma Count
Rate)
Line Items
High Voltage: Sets the high voltage for normal operation. This value is displayed as
a vertical yellow line on the Plateau Plot graph. The Detector Board ID is used to
determine the default HV setting. If the Detector Board is missing, then the default
HV is 650 V on gamma scintillation detectors.
Minimum Volts: Starting level for the plateau plot. Default is 400 V for gamma
scintillation detectors.
Maximum Volts: Maximum voltage for the plateau plot. Default is 1200 V for
gamma scintillation detectors.
Note: High Voltage, Minimum Volts, Maximum Volts and Step Volts settings
are shared with F1 - Optimize Gamma HV test screen (on page 78).
Step Volts: Voltage increment between data collection points. Default is 25 V.
Dwell Time: Time spent at each voltage level during sweep; range is 0.125 – 60.0 s,
default is 1 s.
Maximum Rate: The test stops to prevent detector damage if the count rates reaches
the Maximum Rate (range is 10 cps with no upper limit, default is 2000 cps).
Note: Dwell Time and Maximum Rate are specific to this screen only and not
necessarily shared with the F1 - Optimize Gamma HV test screen (on page
78).
Function Keys
F1 = Collect Plateau Plot: Starts data collection for the selected detector. During
collection, the current settings and count rate are displayed below the plot.
The F1 key description is replaced with “Detector Missing” if the selected detector
board is not responding and will therefore not start collection for that detector.
Recovery is automatic if the detector shows up again (must Esc out of the screen and
re-enter by pressing F9). The plot aborts if the detector goes missing while
collecting.
F2 = Collect all Detectors with same Board ID (Ctrl=All): Pressing F2 collects
data for all detectors whose Board ID matches current detector's Board ID. Pressing
Ctrl+F2 collects data for all detectors (with HV).
Note: All detectors being collected are scanned for the smallest Minimum Volts for
the initial collection voltage and collection continues until the largest
Maximum Volts is reached.