Error Code – Definitions
Reaction Noise (Mean Deviation)
UniCel DxC Systems Instructions For Use A13914
Troubleshooting Calibration and Result Errors
October 2005
Page 13-27
13
Reaction Noise (Mean Deviation)
The average difference between the reaction absorbance readings and the line of
regression is greater than allowed. This checks for constant noise during the spin
cycle. This flag may indicate possible issues with a photometer reading. Also, results
below the low end of the analytical range may trigger the RXN NOISE flag.
Reaction Outlier (Maximum Deviation)
A single reaction absorbance data point, obtained during the reaction read window,
deviates more than allowed from the line of regression. The units are measured in
delta absorbance and will check for noise during the reaction read window. This flag
may also indicate possible issues with a photometer reading.
Reaction Rate High/Low
The rate calculated during the reaction read window exceeds reaction rate limits.
Units are measured in delta absorbance/minute. If a high flag is triggered, dilute the
sample and rerun. If a low flag is triggered, rerun sample for verification. The low
flag may also indicate an old or contaminated reagent cartridge.
It is not appropriate to report a result of ">" or "<" the analytical range of the analyte
for this error code.
Reagent Days Exceeded
On-board reagent has exceeded the usable days. The result should be verified as
acceptable before reporting the value.
Reagent Expired
On-board reagent has exceeded its Lot Expiration Date. The result should be verified
as acceptable before reporting the value.
Reagent Not on Board
Tests could not be run as programmed; reagent was not loaded on the system.
Reference Signal Noise
The difference between the high and low values of the eight reference readings (taken
milliseconds apart) has exceeded the limits allowed. Units are measured in ADCs and
are a measurement of the ISE reference electrode noise observed during the reference
cycle. Consistent flags may indicate poor system grounding. Other causes include
bubbles in reagent, pinched lines, or anything which may interrupt reference reagent
flow.
Rerun Result
Test result is a rerun result.
