Frequently Asked Questions - Fluke Biomedical RaySafe Xi 8201011 User Manual

RaySafe Xi User Manual – Tips and Tricks
Display
LoSignal
HiSignal
LoRange
HiRange
t<delay
Ofl.
Auto range out of order
Offset adjustment out of
range
Offset out of range
LokV
HikV
HiFilt
Battery down
Detector is incompatible

FREQUENTLY ASKED QUESTIONS

What is the difference between R/F high and R/F low, and how do I use them?
R/F low is optimized for low signal levels, typically found during fluoroscopy, behind a phantom. It has a high
sensitivity at the cost of a lower bandwidth (0.1 kHz) and should be used at dose rates below approximately 1
mGy/s.
R/F high is optimized for higher signal levels and features a higher bandwidth (2.5 kHz). It is typically used
before a phantom, and is required for measuring kVp (as opposed to kV).
What is the difference in dose and dose length product in a CT application?
Dose is basically a property of a point in space, while dose length product (DLP) is dose times a length. When
measuring with a 100 mm ionization chamber the following holds true: DLP = (Measured dose in a point and
assuming a homogenous field) • (Slice Width).
Meaning
The dose rate is too low to calculate a value (increase mA or decrease FDD).
The dose rate is too high to calculate a value (increase FDD or decrease mA).
Calculated parameter is less than specified range.
Calculated parameter has exceeded specified range.
The exposure time is not long enough to calculate a value.
Overflow, i.e. calculated value is numerically higher than can be displayed.
At least one of the measuring ranges is out of order.
Hardware offset levels may be out of range due to extreme temperatures.
Ionization chamber current fails to reach a stable level when the RaySafe Xi CT
detector is turned on.
The kV is too low to calculate the total filtration.
The kV is too high to calculate the total filtration.
The filtration is too high to measure the parameter.
The battery must be charged before any measurements can be made.
The connected detector is not compatible with the RaySafe Xi base unit version.
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