Ecotech Acoem Serinus 30 - Clean Pneumatics; Pressure Sensor Check

Serinus® 30 User Manual 3.3
Page 154
6. Back - Diagnostics Menu.
7. Enable - Control Loop → Enabled.
8. Run a manual background.
CAUTION
Not using the correct tool can cause the damage to detector PCA.
6.4.8 Clean Pneumatics
The Calibration Valve Manifold will require disassembling and cleaning. Ideally the valves and the
manifold should be cleaned in a sonic bath with lab detergent and distilled water. Once clean rinse
with distilled water and dry with clean dry oil free air before reassembling. A leak test should be
performed once the instrument is ready for operation (refer to Section 6.4.4).
Note: If the tubing shows signs of significant contamination, it should be replaced with new tubing.
Do not clean the CO-CO
2
converter or the mirrors found within the Measurement Cell.
6.4.9 Pressure Sensor Check
Pressure checks are needed to ensure that the pressure sensor is accurately measuring pressure inside
the instrument.
During normal operation ensure that the pressure and flow menu indicate the following parameters.
Ambient should display the current ambient pressure at site. Cell should indicate current cell pressure
depending on the pump condition and location. The cell pressure is normally about 20 torr below
ambient.
Equipment Required
• Barometer
• Digital Multimeter (DMM)
Procedure
1. Open - Main Menu → Analyser State Menu → Pressure & Flow Menu.
2. Turn OFF the vacuum pump and allow the instrument to return to ambient.
3. Disconnect the exhaust and sample port connections.
4. After 2 - 5 minutes observe the pressure readings: ambient and cell. Ensure that they are reading
the same ± 3 torr (± 0.4 kPa).
5. If the readings are outside this level, perform a pressure calibration (refer to Section 5.2).
If the pressure calibration fails, the instrument may have a hardware fault. The cell pressure PCA has
test points. To determine the condition of the sensor measure and the voltage on the test points, refer
to Figure 141. The voltage measured across the test points is proportional to the pressure measured
by the sensor. If the sensor is exposed to ambient pressure at sea level, the voltage will be around 4
volts but if the sensor is under vacuum, the voltage will be low (e.g. 0.5 volts). If the test point measures
zero or negative voltage, the assembly is most likely faulty and will need to be replaced.