Mindray WATO EX-55, Service Manual

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4.3.6.2 Troubleshoot Electronic Flowmeter Zeroing Failure
In case of zeroing failure, troubleshoot as follows:
1. Disconnect the gas supplies. After bleeding the residual gas inside the machine (or after
adjusting the flowmeter to cause the pointer of the pressure gauge to go to zero),
perform zeroing again.
2. If zeroing is completed, we can conclude that zeroing failure is caused by the three-way
valve mechanical fault. Replace the three-way valve assembly.
3. If zeroing is still failed, we can conclude that zeroing is caused by the three-way valve
hardware circuit fault or electronic flowmeter board fault. Replace the three-way valve
assembly or electronic flowmeter board.
4.3.7 O2 Sensor Calibration (optional)
NOTE
z
Calibrate the O2 sensor again when a great dviation of O2 concentration
monitored value occurs or when the O2 senosr or monitor board is replaced.
z
Before calibration, observe if the O2 sensor displays numerics on the measure
screen. If not, confirm that the O2 measure switch is turned on, check the O2
sensor connection line, or replace the O2 sensor unitl measure numerics are
displayed.
4.3.7.1 Calibration Procedures
For details, refer to the section about O2 sensor calibration in the Operator’s Manual.
4.3.7.2 Commonly-encountered Problems and Recommended Actions
Failure description Possible cause Recommended action
If the alarm [
O2 Sensor
Unconnecte
d] is displayed, it
indicates that O2 sensor is not
connected.
Connect the O2 sensor. After [
Start
] is
selected, calibration
failure is prompted
very soon.
Select the [
Maintenance
] shortcut key
→ [
User Maintenance >>
] → [
Set
O2 Sensor Monitoring >>
]. The O2
sensor is set to OFF.
Set the O2 sensor to ON.