Thermo Scientific DensityPRO NAI Series, Руководство пользователя

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Operation
Detector Screens
Thermo Scientific DensityPRO User Manual 4-35
b. When Disable is selected, no action will be taken.
3. In the Dynamic Tracking Time (sec) textbox, enter a length of time, in seconds, to
perform dynamic tracking.
4. In the Dynamic Tracking Threshold % textbox, enter the dynamic tracking
threshold in a percentage.
5. Choose whether to enable or disable the X-ray hold function by using the X-ray
Threshold Enable dropdown.
a. The X-ray safeguard, calculated at a rate of 10 times per second, computes the
difference between the data counts filtered by the filter time constant and the
counts filtered by the time constant divided by 16. If the difference is greater
than the X-ray safeguard threshold value and X-ray Threshold Enable is
enabled, the X-ray safeguard is active and the high voltage will hold at the last
valid value. The X-ray Safeguard will be active for at least the amount of time
entered in the X-ray Threshold Min Hold Time (sec) textbox. At the end of
minimum hold time, if the count is below the threshold, the hold will be
cleared. If it is still above the threshold, the system will stay in the hold
condition for another cycle of the minimum hold time. The system will
continue to repeat cycles of the minimum hold time, if necessary, until the
time entered in the X-ray Threshold Max Hold Time (sec) is reached. When
the maximum hold time is reached, the X-ray safeguard will be disabled for
one minute to allow the system to recover. Once that minute is up, the X-ray
Safeguard will activate again and respond to future events.
b. When Disable is selected, no action will be taken.
6. Enter the X-ray threshold minimum hold time, in seconds, in the X-ray Threshold
Min Hold Time (sec) textbox.
7. Enter the X-ray threshold maximum hold time, in seconds, in the X-ray Threshold
Max Hold Time (sec) textbox.
8. Designate an X-ray safeguard threshold value in the X-ray Safeguard Threshold
textbox.
9. Enter a time, in seconds, in the Flow Time Constant (sec) textbox.