Lake Shore 370, Руководство пользователя

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Lake Shore Model 370 AC Resistance Bridge User’s Manual
Analog Outputs (Continued)
The next analog output setup screen appears as a prompt for the high endpoint.
Analog Out Setup
Analog Out 1
Enter A Value For
+10V Endpoint: 0.00000 K
Use the data entry keys to enter the endpoint value between 1 × 10
–6
and 100 × 10
6
depending on selected units. Enter the
numeric value first. Press
Enter
to accept the new value and advance to the units multiplier. Use the
s
or
t
key to
select a units multiplier of m, blank, k, or M. Press
Enter
to accept the new selection and return to the normal display.
Press
Escape
to restart the setting sequence and enter a new value. Press
Escape
again to cancel the sequence and return
to the normal display.
Figure 4-3 illustrates the operation of an analog output configured to follow an input channel in Kelvin with a low
endpoint of 0 mK and a high endpoint of 100 mK. Both unipolar and bipolar operation is represented.
Bipolar
–10 V
0 mK
+10 V 0 V
Unipolar
10 V 0 V
Input
Output
Input
Output
5 V
100 mK 0 mK 50 mK
100 mK 50 mK
Figure 4-3. Unipolar Versus Bipolar Analog Output
4.17 STILL OUTPUT
The Model 370 can provide the small amount of power required to drive the still heater of a dilution refrigerator with
analog voltage output 2. None of the analog output hardware changes when it is configured for still operation. Paragraph
3.8.3 describes how to estimate the full-scale current sourced to a resistive heater. When analog output 2 is in still mode,
the
Still
key gives direct access to the still output parameter which is used to set a percentage of the full scale current.
The still output parameter is the same as the manual output parameter in manual mode but the setting can be made
without sequencing through the analog output menu.
To use Analog Output 2 as a still heater output configure the analog output in still mode as described in Paragraph 4.16.
Unipolar operation is recommended for this application. Press the
Still
key and the following screen appears as a prompt
for the output value.
Still Output
Enter A Value For
Still Output: +0.0000 %
Use the data entry keys to enter a still output value –100 % and +100% in bipolar mode or 0 and +100% in unipolar
mode. Press
Enter
to accept the new selection and return to the normal display. Press
Escape
to restart the setting
sequence and enter a different value. Press
Escape
again to cancel the sequence and return to the normal display.
4-32 Operation