Handbook
November 2011
/
59-UMC0071
/
Issue
01
Mercury
iTC
Page 139
LEVEL-METER DAUGHTER BOARD
Original Instructions
NOTE: Select Fast sampling when filling the reservoir. Return the sampling rate to
Slow when the reservoir is full, to conserve helium.
16
If a pre-pulse is required, enter a value between 0 and 160 mA in the
Pre-pulse
Amplitude (mA)
field.
17
If a pre-pulse is required, enter a value in seconds in the
Pre-pulse Duration (s)
field.
18
Tap
Home
to return to the Home page.
19
If required, access the Channel Display Configuration page and change the
displayed value from
Resistance
to
He Level
.
16.3.2
Configuring a liquid-nitrogen sensor
1
Tap an unconfigured panel on the Home page. The Channel Display Configuration
page is displayed.
2
Tap on the
Devices
field and select a level meter input.
3
Tap on the
Signals
field and select
Pulse
.
4
Tap
Assign
to save the changes.
5
Tap
Home
.
6
With the nitrogen sensor at room temperature, record the sensor frequency that is
displayed on the Home page.
7
Fully immerse the sensor part of the probe in liquid nitrogen.
8
Record the sensor frequency that is displayed on the Home page.
9
Tap the configured level-meter panel on the Home page. The Level Meter Sensor
Details page is displayed.
10
Select the
Nitrogen
tab.
Figure 16-4
Level Meter Sensor Details page - Helium tab
11
Enter the frequency measured in step
in the
Frequency at 0% (Hz)
field.
12
Enter the frequency measured in step
in the
Frequency at 100% (Hz)
field.