Julabo

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Julabo is a temperature control unit. There are many different versions. The commands are slightly different I have made a record in this spreadsheet.

In general they control the temperature by pumping a fluid from a temperature controller bath to the sample and back. It is possible to connect an external sensor to the unit and have it control the temperature from this sensor or have it control itself from the internal bath temperature.

Setpoints

The Julabo device only has one setpoint. To enable cset to be used with blocks pointing at either internal or external temperature, there are aliases from EXTTEMP:SP to TEMP:SP. This does mean as a user I can set the setpoint for the wrong item I am controlling (e.g. mode is external control but the user set the temperature on temp) but this is better than:

1. Having an alarm on the pv when the wrong setpoint is used because it relies on the the control mode read back value being up-to-date
2. Setting the setpoint dependen onthe control mode because it relies on the control mode being up-to-date or on change sending a temperature change to the device; on startup this could be 0
3. Having a unique setpoint PV because then user can not have a single block which is their sample temperature and legacy scripts already use the setpoint block.

P, I and D

The Julabo has PID setting for temperature control and both the internal and external sensors (6 parameters in total). On at least one model (He) setting these using the remote interface, e.g. from IBEX, does not cause the unit to store these values. This means that on a power cycle it resets the values it had to the ones that were last set using the interface on the device. Furthermore from ticket 3104 these values can not be set on startup using either autosave or default PVs in a config.