The RedLion T16xxx is a stand alone loop controller. Most single loopers will do either on/off control or PID control. It will certainly do PID control for tank temperature. but it won't do cascade control which is frequently used for jacketed vessels. It has its own interface, its own HMI, so the setpoint can be changed and the temperature displayed. Depending on what you use for level sensing, one of these will work if the sensor is continuous (4-20mA) but it will not work for discrete point level switches. But there are simple control modules that will do pump-up or pump-down that work with point level switches. Single loopers program from the front panel, software is not needed.
The Red Lion CSM is a modular controller. It is a PAC (Process Automation controller), more targeted at PID process control than fast (mS) discrete automation, a good fit for temperature and level control. It is a controller module, it needs a power supply and I/O modules, depending. An HMI display is needed for temperature/level display and to be able to change the setpoint. RedLion sells HMI displays, too. Software is needed for configuration. Last time I looked, Red Lion software for the HMI was free, I think it is for this unit, too.
The PLC is a PLC. You buy the needed I/O modules and program the PLC to do what's needed. PID control (as opposed to any on/off control) is quite common on PLCs nowadays. I don't know if any particular Mitsubishi model does PID. An HMI is needed for temperature/level display and to be able to change the setpoints, which needs its own programming. Software is needed to program the PLC and the HMI. Many PLC vendors charge for software.
