Fluke Biomedical 8000 Victoreen - Manual (Page 69)

Victoreen 8000
Operators Manual
4-8
4.3 Error Messages
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The measured quantity (time and/or exposure) cannot be calculated. This typically occurs along with the
High or Low kVp error messages. If the kVp is more than 10% above or below the selected kV filter
range, the NERO mAx cannot accurately calculate kVp. When this happens, the NERO mAx cannot
measure exposure time between the selected %kV points on the kV waveform and cannot correct the
measured exposure based upon kV. To remedy this situation switch to the next higher or lower filter
range based upon the High or Low kVp messages. This error is automatically cleared when an exposure
is made that is within the selected kVp range.
%kV TOO LOW
If the NERO mAx cannot find the selected %kV on the kV waveform, a %kV TOO LOW message is
displayed. This occurs when the kVp of an exposure is so low that the kV at the selected %kV is less
than 80% of the minimum kV of the selected kV filter range. For instance, if an exposure is made at 51
kVp using the 50 - 100 kVp filter with the %kV set at 75%, the NERO mAx cannot calculate exposure time
because 38.25 kV (75% of 51 kVp) is below 40 kV (80% of the minimum kV of the 50 - 100 kV filter). To
resolve this situation, select a higher %kV or switch to the next lower filter range.
BATTERY LOW
The battery charge is getting low. This message comes on when there is approximately 20 minutes of
battery life remaining. This error message is cleared a few minutes after the AC adapter is plugged into
the NERO mAx. If this message is ignored and the batteries are allowed to discharge below a safe
operating level, the NERO mAx will become inoperable and the Low Battery indicator on the front panel
will illuminate. (See Section 1.4--Battery Operation and Charging.)
Blinking HIGH or LOW
The measured kVp is above or below the selected kV filter range but still within 10% of the filter’s kV
range. To remedy this situation switch to the next higher or lower filter range based upon the High or Low
kVp messages. This warning is automatically cleared when an exposure is made that is within the
selected kVp range.
CALIBRATION CHECKSUM ERROR
An error has been detected in the calibration coefficients that have been stored in the NERO mAx. The
NERO mAx is not usable in this state and must be returned to Fluke Biomedical for repair. Please
contact Fluke Biomedical at 440.248.9300 for assistance.
DELAY TOO LONG
The programmed measurement delay is longer than the x-ray exposure that has just been made. Verify
that the set exposure time is longer than the programmed measurement delay. This error is cleared
when an exposure is made that exceeds the programmed delay.
This error may occur when the NERO mAx only “sees” part of an x-ray exposure. This can happen when
exposures are made near the NERO mAx’s limit of detectability and only a portion of the exposure is
above the instrument’s threshold. To remedy this situation, switch to high sensitivity, switch to the next
lower kV filter range (if the kV is still within range) or decrease the distance between the detector and the
x-ray tube.
This can also be caused by an x-ray exposure that stops prematurely for more than 20 milliseconds.
When this occurs, the NERO mAx assumes that the exposure is complete after 20 milliseconds.
EXPOSURE TOO LONG