Roche cobas b 221 system User Manual

Roche Diagnostics May 2009
Service Manual · Version 9.0 A-37
cobas b 221 system 2 Fluid actions
Calibration
Mix1 Calibration This section refers to the BG and ISE measuring chamber only. The Mix1 mixture is
prepared similarly to a recalibration in the sample distributor after a measurement
and is ready for entry to the measuring chamber at V21.
e For more information, see Recalibrating BG/ISE and drying tHb/SO
2
or COOX on
page A-29.
The main pump first aspirates a mixture of air (from a reservoir between sample
distributor and measuring chamber cartridge) and Mix1 through the measuring
chambers. When this has sufficiently washed them, the measuring chambers are filled
with Mix1 by shutting off the air feed.
This filling is assessed by conductivity measurement: with liquid solution a stable and
plausible value must be measured between MCI and MCO.
Then the inlet valves are closed and reference solution is aspirated through valves V5
or V9 until a clear increase in conductivity between MCI and MCO can be detected.
Finally the outlet and reference valves are closed and the conductivity is checked
again.
Mix2 Calibration The fluid procedure corresponds exactly to the Mix1 calibration.
The only difference is the mixture ratio of CAL A and CAL B:
The Mix2 calibration determines the slopes of the BG electrodes CO
2
and pH along
with all ISE electrodes.
Mix1: 33.3% CAL A
66.6% CAL B
Mix2: 60.0% CAL A
40.0% CAL B

Roche cobas b 221 system Specifications

General

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