Mindray WATO EX-55, Service Manual

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11. Adjust the O2 flow regulator until O2 flow is approximately 0.5 L/min, causing the
reading on the test pressure gauge to fall gradually to 0.2 MPa (2bar).
12. Turn off O2 flow to cause the reading on the test pressure gauge not to fall. If the
“Drive Gas Pressure Low” alarm occurs 10 s later, it indicates that the pressure switch
on the integrated pneumatic circuit of the expiratory valve assembly is faulty.
Troubleshoot this problem as described in the relevant failure table.
13. Adjust the O2 flow regulator until O2 flow is approximately 0.3 L/min, causing the
reading on the test pressure gauge to fall gradually to 0.15 MPa (1.5bar).
14. Turn off O2 flow to cause the reading on the test pressure gauge not to fall. If the “O2
Supply Failure” alarm does not occur 10 s later, it indicates that the pressure switch of
the O2 supply inlet assembly is faulty. Troubleshoot this problem as described in the
relevant failure table.
15. Adjust the O2 flow regulator until O2 flow is approximately 0.3 L/min, causing the
reading on the test pressure gauge to fall gradually to 0.05 MPa (0.5bar).
16. Turn off O2 flow to cause the reading on the test pressure gauge not to fall. If the
“Drive Gas Pressure Low” alarm does not occur 10 s later, it indicates that the
pressure switch on the integrated pneumatic circuit of the expiratory valve assembly is
faulty. Troubleshoot this problem as described in the relevant failure table.
5.3.2.3 Adjust the Pressure Switch
Adjust the O2 supply pressure switch and drive gas pressure switch as described below.
For the convenience of operations, disassemble the corresponding assembly. Take the O2
supply pressure switch as an example. Use a flathead screwdriver to adjust the O2 supply
pressure switch as shown below. Turn for small degrees each time such as 30 degrees. Note
that turning the pressure switch clockwise will decrease its alarm limits and
counterclockwise increase its alarm limits. Assemble the assembly after each pressure
adjustment is made and perform a test. Repeat the operations until the pressure at the time
moment when the alarm occurs meets the requirement.