We have a 335 in the lab at Stockholm University and I want to use the autotune feature. When pressing the 8 (autotune) key I get to choose my input, but there is no up or down arrow and I can't choose anything but input B, which isn't the one I'm using. Of course, I could switch to B but now I have A properly set up. Anyone know what's going on?
Post by Lake Shore Jeff M on Apr 25, 2019 12:33:32 GMT -5
What Control Input do you have assigned to Output #1? With Input A assigned to Output #1 and Input B assigned to Output #2, I can select Input A or B for the Autotune. When starting Autotune, make sure the setpoint is greater than and no more than 5 degrees higher than the control input temperature
So i've tried inputa A with output 1, in which case I could only select input B for autotune, and input B with output 1, for which I instead got a message saying "no control loops" or something similar. After I choose my control loop, the machine should check if initial conditions are met but I can't even get that far.
Post by Lake Shore Jeff M on Apr 26, 2019 7:03:50 GMT -5
Something definitely is not working correctly so I suggest you do a factory default reset as described in section 8.7 of the user manual. Before doing this, make sure to record the Input, Output and Display Setup values as they will be cleared. You do not need to clear the curves when you perform the reset. Once the reset is completed, reconfigure the Input and Output setup and see if the correct input can be selected for Autotune. If not, the 335 may need to be returned to the factory for analysis.