ABL77 Service Manual Chapter 4: Test and Calibration Procedures
Electronic Zero Offset, Continued
Verify zero
offset
(continued)
Step Action
6.
Press Set 0 to zero all channels
7.
• The O2(nA) channel should fall within -0.010 to +0.010 nAmps.
• The pH, CO
2
, and ISE channels should fall within –0.1 to +0.1 mV
• The Hct channel should fall within –20 to +20 AD counts
• The Th channel should read 36.5 to 37.5
8.
Remove the zeroing cassette.
• The pH, CO
2
, and ISE channel values will begin to “float”. This is
normal and expected.
• The Hct channel should remain at zero (±20)
• The Th channel should read 100
• The O
2
channel should remain at zero (±0.010)
9.
• If the Hct channel does not remain at zero, replace the analog board
• If the Th channel does not read 100, replace the analog board
• If the O
2
channel does not remain at zero, first replace the valve
board. If this does not solve the problem, replace the analog board.
Rev. F 4-35