Philips M3000A, Service Manual

Page: 163 / 293

Preventive Maintenance Tests
Testing the Instrument 147
Step 4 Select “Close Valves: On”
Step 5 Raise the pressure to 280 mmHg with the manometer pump.
Step 6 Wait 10 seconds for the measurement to stabilize.
Step 7 Compare the manometer values with the displayed values.
Step 8 Document the value displayed by the M3046A (x1).
Step 9 If the difference between the manometer and displayed values is greater than 3
mmHg, calibrate the Server. If not proceed to the Leakage test.
Step 10 To calibrate, select “Close Valves off” then “Calibrate NBP” and wait for the
Instrument to pump up the expansion chamber.
Step 11 When pumping has stopped, wait a few seconds until “EnterPrVal” is highlighted
and then move the cursor to the value shown on the manometer.
NOTE If one of the following prompt messages appears during this step, check whether there is
leakage in the setup:
— NBP unable to calibrate–cannot adjust pressure
— NBP unable to calibrate–unstable signal
Step 12 Press Confirm.
NOTE If the INOP NBP Equipment Malfunction message occurs in Monitoring Mode, go back to
Service Mode and repeat the calibration procedure.
NBP Leakage Test
This test checks the integrity of the system and the valve. The NBP leakage test is required
once every two years and when the Instrument is repaired or when Instrument parts are
replaced.
Step 1 If you have calibrated, repeat steps 2 to 6 from the Accuracy test procedure so that
you have 280 mmHg pressure on the expansion chamber.
Step 2 Watch the pressure value for 60 seconds.
Step 3 Calculate and document the leakage test value (x2).
x2 = P1 - P2
where P1 is the pressure at the beginning of the leakage test and P2 is the pressure
displayed after 60 seconds.
The leakage test value should be less than 6 mmHg.