User guide

328 Advanced User Guide
10 Detectors
Detector off When the detector is off, Adjust offset and Bead
voltage are Off and initial Output is displayed.
Detector on—detector temperature less than 150 °C. When you
enter an Adjust offset value or press [On], detector gases turn on
and the display blinks the Temp not ready message.
Detector on—waiting for oven and/or detector to reach temperature
setpoint and equilibrium.
If the oven or detector is not at
setpoint, the display continues to blink the Temp not ready
message.
Detector on—Dry Bead On If Dry Bead is On, the temperature rise
holds at 150 °C for 5 minutes to remove moisture, then
continues to the setpoint.
Detector on—during adjust offset. When the detector and oven
temperatures reach setpoint and equilibrate, the Adjust offset
process begins. The bead voltage is slowly increased until the
output is close to the Adjust offset value. The display blinks
Detector Slewing.
Detector on and ready. When the Adjust offset value is reached,
the Adjust offset line reads Done and displays the offset target
setpoint. Your detector is on and ready. The display shows the
actual Bead voltage.
Setting NPD adjust offset on the clock table
You can use the Clock table feature to begin Adjust offset at a
specified time.
Aborting NPD adjust offset
Press [Delete] with the cursor on the Adjust offset line. This
cancels the adjustment without turning off the detector gases
and bead voltage.
Extending the NPD bead life
These actions, together with the automated heatup and adjust
procedures, can extend ceramic bead life considerably.
• Use the lowest practical Adjust offset value. This will result in
a lower Bead Voltage during operation.
• Run clean samples.
• Turn the bead off when not in use.