RaySafe Xi - Manual (Page 44)

Display Meaning
Losignal the dose rate is too low to calculate a value (increase ma or decrease fdd).
hisignal the dose rate is too high to calculate a value (increase fdd or decrease ma).
Lorange Calculated parameter is less than specified range.
hirange Calculated parameter has exceeded specified range.
t the exposure time is not long enough to calculate a value.
ofl. overflow, i.e. calculated value is numerically higher than can be displayed.
auto range out of order at least one of the measuring ranges is out of order.
offset adjustment out of
range hardware offset levels may be out of range due to extreme temperatures.
offset out of range Ionization chamber current fails to reach a stable level when the raysafe Xi Ct
detector is turned on.
LokV the kV is too low to calculate the total filtration.
hikV the kV is too high to calculate the total filtration.
hifilt the filtration is too high to measure the parameter.
Battery down the battery must be charged before any measurements can be made.
detector is incompatible the connected detector is not compatible with the raysafe Xi base unit version.
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).
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raysafe Xi user Manual – tips and tricks