Lake Shore Model 321 Autotuning Temperature Controller User’s Manual
3-20
Operation
3.4 INTERFACE AND MISCELLANEOUS FUNCTIONS
The following front panel keyboard function are related to the thermometry or temperature control
aspects of the Model 321.
Function Paragraph
Baud ..............................3.4.1
Analog Out.....................3.4.2
Defaults/Reset...............3.4.3
PUP ...............................3.4.4
3.4.1 Baud
If using the Serial Interface, the use must set the Baud rate. Pressing the
Baud
button brings up the
following display.
Use either the
s
,
t
, or
Baud
button to cycle the selector arrow (
→
) between choices. The available
selections are 300 or 1200 Baud, with 300 being the default. Press
Enter
to accept the new Baud
rate or
Escape
to return the normal display and retain the old setting. Other communication
parameters are fixed as listed in Table 4-1.
3.4.2 Analog
Out
The Analog Output provides a 0 to 10 volt (1 mA max) output that corresponds to the temperature
reading. The default analog output has the 0 to 10 volts corresponding to 0 to 1000 K. The resolution
is 1.22 mV (0.122 K) and the accuracy is ±0.04% of full scale measurement accuracy. The
user also has the option to rescale the analog output; assigning new temperatures (in kelvin) to
correspond to 0 and 10 V (minimum temperature resolution is 0.1 K).
To program the analog output, press the
Analog Out
button. You will see the following display.
The default selection is default, where the 1 to 10 volt output will correspond to 1 to 1000 K. A
different (narrower) temperature range may be selected by using either the
s
,
t
, or
Analog Out
button to cycle the selector arrow (
→
) to User. Upon pressing the
Enter
button, you will see the Enter
Maximum display. For this example, we will use the numeric keypad to enter a maximum temperature
of 300 K. After making this entry, you should see the following display.
Press the
Enter
button. The Enter Minimum display will now appear. For this example, we will use the
numeric keypad to enter a minimum temperature of 2 K. After making this entry, you should see the
following display.
