Lakeshore340

Lakeshore 340

The lakeshore 340 is a device used by LET to monitor the temperature of a sample when it is being cooled by a dilution fridge inside the 9T magnet.

This lakeshore has four measurement channels, each of which exposes a temperature and a raw measurement (usually a resistance from a thermocouple). The device supports multiple independent temperature control loops, however we only use one of these loops.

The device itself has a large amount of functionality, however the IOC (and corresponding labview driver) only expose a fraction of it. The functionality exposed by the drivers is:

• Set and read back a temperature setpoint (it only ever sets and reads back the setpoint for control loop 1).
• Reads 4 temperature channels
• Reads the "raw" (resistance) measurements from these same 4 channels
• Set and read P, I and D values
• Set and read the PID mode (one of Manual PID, Zone, Open Loop, Auto-tune PID, Auto-tune PI or Auto-tune P)
• Set and read whether the control loop is on
• Set and read the maximum temperature setpoint
• Reads the heater output as a percentage
• Set and read maximum heater power as a percentage

Terminators are CR LF

Device uses a 9-way male serial cable (female connector on device) and requires a null modem.