Thermo Scientific Sarasota SG901, User Manual

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Maintenance
Preventive Maintenance
Thermo Fisher Scientific Sarasota SG901 User Guide
6-3
Figure 6–1.
Pressure transmitter with cover removed
You can check the condition of the filter by removing the element and
visually inspecting it or by varying the flow through the system and noting
the change in pressure. To check the filter using flow:
1. Set the flow to 5 L/min and note the pressure.
2. Change the flow to 10 L/min. Pressure should not change by more
than 0.02 bar (0.3 psi).
Follow the steps below to check the density sensor.
1. Set the valves for validation, and purge the system with dry air at low
pressure.
2. After several minutes, disconnect the supply while closing valve 4
(reference Figure 4–1 ).
3. Allow the pressure to drop to atmospheric conditions.
4. When stable, record the density meter period. This period (adjusted for
temperature using the temperature coefficient published on the
calibration sheet and for the change in density of air at the test
conditions) should be within 200 nsec of the Tair published on the
sheet. If the Tair is not within specification, the density meter sensor
requires cleaning. Refer to the density meter’s manual.
If there are no problems, put the system back into service.
Filter Condition
Density Sensor
Check