Roche cobas b 221 system User Manual

Roche Diagnostics May 2009
D-124 Service Manual · Version 9.0
7 Troubleshooting cobas b 221 system
Important test routines
Following items will be displayed in case of nOk – .
The standard deviation is shown as number of errors in the selected period. For each
parameter, the following limit (in percentage) applies:
Standard deviation spec.
Similar to the electrode voltage scanning. Evaluates the measuring quality (standard
deviation) of several single measurement points of the electrode adjusting curve. If
the standard deviation increases with the distance to the reference electrode, cross
currents are concerned. If the standard deviation is insufficient at all ISE electrodes
the reference electrode is concerned or air bubbles are present in the sample path.
Possible error causes: defective measuring chamber electronics, defective reference
electrode, wetting problems.
Following items will be displayed in case of nOk – .
The standard deviation spec. is shown as number of errors in the selected period. For
each measuring chamber, the following limit (in percentage) applies:
Stability monitor limits
The stability monitor uses smaller limits than the applied limits to the instrument in order to
recognize problems at an early stage.
Item Description
Parameters
affected parameters
Standard deviation
number of parameter messages
Interference
number of parameter errors
Ta bl e D -1 3 Standard deviation details
Sensor Limit value
all < 10 %
Ta bl e D -14 Standard deviation evaluation
Item Description
Meas. chamber
affected measuring chamber
Each parameter may be listed more than once due to different
electrode status messages.
Standard deviation
number of measuring chamber messages
Interference
indication of the error;
h press "Details" for troubleshooting information
Error
number of measuring chamber errors
Ta bl e D -1 5 Standard deviation spec. details
Meas. chamber Limit value
all < 10 %
Ta bl e D -16 Standard deviation spec. evaluation

Roche cobas b 221 system Specifications

General

Brand	Roche
Model	cobas b 221 system
Category	Medical Equipment
Language	English