EUROTHERM 'S 3216 one-sixteenth DIN controller can now be fitted broadcast Modbus master communications. This allows it to act as a setpoint master for zone control applications including multi-zone profiling and cascade control using a second controller.
Broadcast master communications allows the controller to send a single value to any slave instrument using a Modbus broadcast function. This allows the 3216 to link through digital communications with other products without the need for a supervisory PC. The facility provides a simple and precise alternative to analogue retransmission, without the risk of errors due to analogue conversion. The retransmitted parameter can be selected from setpoint, process variable, output demand or error.
The controller can also provide an eight-segment setpoint program, allowing basic heating control systems to economically incorporate a heating profile. The program feature also allows for digital outputs which can be linked to relays to advise of end of program status or run mode.
The program feature is configured using the iTools wizard, and can be set for all standard functions such as step, ramp and dwell, plus advanced features such as holdback, which ensures the process holds the process to temperature. On starting the program, users can select a smart start by beginning at the current ambient temperature. The program end can be set for dwell or reset.
The 3216 provides for five stored calibrations. These can be recalled to instantly reconfigure up to 38 stored configuration settings. These settings allow up to five different programs to be stored, including program descriptions.
The 3216 can be fitted with up to three outputs, including relay, logic and analogue. The logic output can also be software-configured as a digital input if required. A further digital input for alarm acknowledgement or program start can be fitted as part of the plug-in communications slot.
The optional plug-in serial communications options of Modbus RS232 or RS485 allow interfacing with higher level systems or other master control systems. An additional digital input and current transformer input are also provided for monitoring other process inputs.
The three-colour LCD display provides a clear indication of process variables. The upper display shows the process measured value while the lower display can be set to display a range of parameters including setpoint, time remaining and current. The system provides scrolling safety messages to advise operators and engineers of exactly what is happening to the process.
Applications include simple heating and cooling, small ovens, chillers, sterilisers, trace heating, heat sealing and injection moulding.