HJC黄金城

DESCRIPTION

PCT40 BASIC PROCESS CONTROL SYSTEM

The PCT40 contains everything that is needed to perform a range of single-loop process control experiments in conjunction with a PC.

It includes a variable volume process tank, a hot water tank with electric heater and indirect heating/cooling coil, a hot water pump, two non-dedicated pumps, three on/off solenoid valves and a proportioning valve. The instrumentation includes temperature sensors, two differential water pressure sensors, a mechanical level sensor (float switch) and an electronic level sensor (conductivity). The inlets and outlets of the various pumps, valves and tanks incorporate self-sealing quick release fittings. This enables the configuration to be quickly changed, offering a wide variety of different loops.

The PCT40 includes a computer interface (USB), and all of the parameters can be controlled directly from the computer, (i.e. the pump speeds, the valve positions and the heater power). The computer also displays the readings from the various measurement sensors.

The software supplied with the unit includes on/off, time proportioned and proportional/integral/derivative (PID) algorithms where all the parameters are easily accessed and adjusted by the user. This approach means that a separate electronic console is unnecessary for most applications.

The flexible nature of the system also enables a wide variety of different disturbances to be applied to the loops to permit the effectiveness of the control parameters to be compared. As all these disturbances are under software control, they can be repeated precisely during the optimisation process, thus enabling an excellent degree of fine-tuning to be implemented.

A pressure regulating valve with filter is also included to isolate the equipment from fluctuations in the water supply pressure.

The type of loops achievable with the basic PCT40 include:

•  Tank water level by varying input flow
•  Water flow rate by varying pump speed
•  Temperature of water in a vessel by varying the heater power
•  Temperature of water heated indirectly by varying the flow rate