Temperature Stepping and Ramping in LabView
The Cryostation boasts a 10W platform heater allowing users to easily manipulate the platform and sample temperatures between 3K and 350K. This can be done in Manual Mode by changing the temperature set point, but more easily using an external script control such as LabView. This allows for stepping to various temperatures, getting to higher temperatures quicker, and ramping the temperature with control.
The data below demonstrates the capability of stepping through temperatures. To create this graph, the system was configured in the standard configuration with no options. The system was cooled down to base temperature and then run with a LabView script to step from 10K to 350K in increments of 10K. The script ran the temperature at each set point for 10 minutes. The new software has custom PID settings for several zones. Depending on the target temperature the PID will adjust to the zone that it falls into. There are several PID zones defined as a default, but the user can add more zones if they would like. Once settled at target temperature, which takes a few minutes, the temperature stability was less than 10mK at most set points. Note: Different option configurations may yield different temperature stability results for the sample thermometer, as well as time to target temperatures.
To create a fairly uniform ramp in temperature a script was written to ramp in steps of 0.1K from base temperature to 350K in 10 second intervals. Again, the system was configured in the standard configuration and cooled to base temperature first. Ramping of temperatures allows for the study of detailed transitions to be explored.