Lake Shore Cryotronics 121, User Manual

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3.5.4 User Current
Through the computer interface the Model 121 can be programmed to a
current that is between the fixed ranges. This user current is between
100 nA and 100 mA with three digits of resolution. Refer to Chapter 4 to
configure the user current setting. When the user range is selected,
pressing
+/- will change the polarity of the user current, but will not
affect the fixed ranges. Refer to section 3.5.3 for more information. The
user range is selected by pressing

when in the 100 mA range. The dis-
play will then flash “USER” once, then it will flash the user current value
twice before setting the user current.
User Current: ±100 nA to ±100 mA
Default: +100 nA
Interface Command:
SETI
3.5.5 Power Up Enable
The power up enable feature allows the user to choose whether or not
the heater range is turned off each time the instrument power is cycled.
Setting the Power Up Enable parameter to Off ensures that the Heater
Range is turned off on power up. Setting it to On will return the heater
range to its previous setting when power is restored.
Interface Command:
PWUPENBL
3.6 Power Up State
The Model 121 can be programmed to power up in a user defined state
called the power up state. The power up state consists of three setup
parameters: range, polarity, and user current value. To save the power up
state, configure the instrument with the desired settings, then press and
hold
+/- for 3 s. To save it through the computer interface, refer to chap-
ter 4. The power up state will match factory defaults after a factory reset.