Mindray WATO EX-55Pro, Service Manual

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8.5.8 Diagnosing PEEP Safety Valve Exceptions
If the PEEP safety valve is in the normally closed state and the gas source complies with the
regulations, the alarm Drive Gas Pressure Low will be triggered.
You can check whether the status of the PEEP safety valve and PEEP valve is correct in the
Diagnostic Tests
menu.
 Perform the following operations to diagnose the status of the PEEP safety valve:
1. Ensure that the gas source complies with the regulations.
2. In the
Diagnostic Tests
menu, if the PEEP safety valve is in the ON state, a gentle
buckling sound will be heard.
3. Change the D/A value of the PEEP valve so that the pressure measured by the PEEP
pressure sensor is larger than 0 cmH2O.
4. Turn off the PEEP safety valve. The pressure measured by the PEEP pressure sensor
should decrease to 0 cmH2O immediately. Turn on the PEEP safety valve. The
measurement value of the PEEP pressure sensor quickly resumes to a value close to that
before the PEEP safety valve is turned off.
During this process, there is flow at the exhaust port at the PEEP end when the PEEP
safety valve is turned on or off, and the flow changes. This can help determine whether
the PEEP safety valve is turned on or off correctly.
5. For any errors, the drive voltage on the PEEP safety valve or VCM is faulty. You can
measure the drive signal (at the corresponding socket) corresponding to the PEEP safety
valve on the VCM by using a multimeter. If the PEEP safety valve is in the ON state,
the drive voltage should be close to 6 V.
If the PEEP safety valve is in the OFF state, the drive voltage should be close to 0 V.
If the preceding conditions are met, the VCM operates properly.
6. If the PEEP safety valve is faulty, replace the inspiratory valve. After replacement, you
can check whether the problem is solved by using similar methods.
8.5.9 Diagnosing PEEP Proportional Valve Exceptions
If the PEEP valve is faulty, a pressure related alarm will be generated in mechanical ventilation
mode.
You can check whether the status of the PEEP valve is correct in the
Diagnostic Tests
menu.
 Perform the following operations to diagnose the status of the PEEP valve:
1. Ensure that the gas source complies with the regulations. Access the
Diagnostic Tests
menu and set the PEEP safety valve to the ON state.
2. As the D/A value of the PEEP valve increases, the value measured by the PEEP pressure
sensor (or calibration equipment of the anaesthesia machine) should also increase. Note