Roche Diagnostics May 2009
A-34 Service Manual · Version 9.0
2 Fluid actions cobas b 221 system
Calibration
O
2
zero point calibration
This procedure determines the second calibration point of the O
2
electrode. The O
2
zero point solution is in the S2 Fluid Pack and is aspirated into the BG measuring
chamber with the vacuum pump and the main pump through the T&D disk (position
5) and the aspiration channel through SS2 and SS1.
After completing this procedure the measuring chamber area is briefly washed.
e
For more information, see Washing the measuring chamber vicinity on page A-27.
A Main pump
B O
2
electrode
C T&D module (position 5)
D Waste separator
E O
2
zero point solution
Figure A-19 O
2
zero point calibration