Servomex NanoTrace DF-760E, Instruction Manual

Page: 52 / 182

48 DF-760E User Interface
and hit the
Enter
key to begin the isolation process. The Isolate Sensor Warning will
appear for 40 seconds.
Figure 19: Isolate Sensor Warning
While the moisture cell is isolated from gas flow, a warning will appear in the lower left
corner of the main display indicating “
Isolated
”. Under this condition, the pressure alarm
is disabled.
CAUTION
Before restoring flow to an isolated moisture cell, be sure the
pressure at the outlet is at or below the cell pressure at the time of
isolation to avoid back diffusion of ambient air from the outlet into
the cell.
CAUTION
When in isolation mode the moisture cell’s pressure transducer will
yield an incorrect reading of the actual cell pressure. Because the
displayed moisture reading is dependant upon a proper pressure
reading, moisture readings should be ignored while the cell is
under isolation.
NOTE: Under these conditions, the pressure alarm is disabled.
7.5.1.2 Gas Valves Control
The moisture gas valves control screen as shown in Figure 20 is used to control the flow of
gas through the moisture cell.
In addition, three options exist for gas valve control. Use the arrow keys ( and

to
move between the selections. After highlighting your choice use the Enter key to move to
the
Apply
button, and hit
Enter
again to apply your choice. The gas valves screen will stay
visible, allowing other changes until the
Next
key is used to highlight the
Done
button,
and the Enter key is hit to return to the main display.

Isolating Sensor closes the upstream and downstream valves for the moisture cell.
This is done to prevent contamination of the cell when in transport or for changing
process lines.

Restore Process Gas Flow opens the upstream and downstream valves of the
moisture cell to allow for gas flow from the sample inlet for normal operation.

Restore Zero Gas Flow diverts the sample inlet flow through the gas purifier and
then through the moisture cell. Flowing the sample through the purifier is