ABL77 Service Manual
Chapter 4: Test and Calibration Procedures
SC/Hematocrit Circuits,
Continued
Calibrate the
SC/Hct circuits
Follow the steps below to calibrate the hematocrit and SC circuits.
A Valve Board Calibration Cassette (REF: 920-729) is necessary to perform this
calibration.
Step Action
1.
Set the electronic zero offset. Refer to the procedure further in this
chapter.
2.
•
Turn off the analyzer and disconnect from the AC power source.
•
Remove the lower module housing from the analyzer. Do not
disconnect cabling.
3.
Install the
Valve Board Calibration Cassette
onto the cassette nest
of the analyzer.
4.
•
Connect the analyzer to AC power and turn the analyzer on
•
Return to the
Hardware
screen
•
Select
Hct(A/D)
from the
Hardware
screen drop-down list.
5.
Adjust
R18
on the valve board until the Hct(A/D) value equals 1390
±
5.
NOTE:
The Hct potentiometer has a typical adjustment range in
excess of 1390
±
50.
6.
If unable to reach the target value, perform the
Calibrate 5 volts
procedure in a proceeding section of this chapter.
7.
If, after calibrating the 5 volt supply, the Hct value CANNOT be
adjusted within the target range, replace the valve board.
•
If, after replacing the valve board, the Hct value still CANNOT be
adjusted within the target range, replace the analog board.
8.
Select
SC(A/D)
from the
Hardware
screen drop-down list.
9.
Perform one of the following two instructions:
•
For the older valve board / manifold assembly, adjust
R1B
on the
valve board until the SC(A/D) value reaches 1109
±
5.
•
For the newer valve board with replaceable valves, adjust
R2
on the
valve board until the SC(A/D) value reaches 1109
±
5.
NOTE:
The SC potentiometer has a typical adjustment range in
excess of 1109
±
400.
10.
If unable to reach the target value, perform the
Calibrate 5 volts
procedure. If the 5 volt output supply has already been verified,
replace the valve board.
Rev. F
4-33