Microprocessor setpoint programmer and controller, format 48×96 / 96×96 (1/8 DIN – 1/4 DIN).
Manufactured using SMT, the instrument provides a complete operator interface, protected by a Lexan membrane that ensures level IP65 faceplate protection.
It has 4 keys, two green LED displays, each with 4 digits, 4 red indicating LED’s for the 4 logic or relay outputs, and a further 3 LED’s that are programmable to indicate the various operational states of the instrument.
10 led red bargraph indication can be associated with analogue outputs for control, inputs or deviations.
The main input for the process variable is universal and provides the possibility to connect many types of input sensor: thermocouple, resistance thermometer, thermistor, linear inputs, potentiometer, all with the possibility of custom linearisation that can be defined using the faceplate keys. The type of input is selected from the faceplate keys and no external shunts or adapter are required.
A second auxiliary isolated analogue input is available, which can also be configured for a linear input, potentiometer or current transformer.
There are two isolated digital inputs for entering the program commands of start, stop and reset, choosing the program and to step through the program.
The instrument can have up to 4 relay (5A/250V) or logic (11Vdc, 20mA) outputs and up to 2 islolated analogue outputs in voltage or current.
The function of each output is configurable and event outputs linked to the individual program step as well as control and alarm functions can be provided.
A further isolated output (10 or 24Vdc, 30mA max.) is available for powering external transmitters or potentiometers. The serial communication interface RS485 (RS232C compatible) makes it possible to read or modify any parameter and to govern the instrument online (local/remote manual/automatic commutation, internal timer control, direct control of outputs).
Protocols available: MODBUS RTU and CENCAL (Gefran).
The sequence for setting up the programmer is particulary brief and there are up to 8 steps, each with a setpoint ramp and hold.
It is also easy to set up any interlocks required from logic inputs and the event outputs, as well as the type of restart preferred using the few set-up steps in the “Step” menu.
The various steps can be regrouped in 4 different programs.
All the programming procedures of the instrument are facilitated by the grouping of the parameters in function blocks (CFG for the control parameters, Inp for the inputs, Out for the outputs, etc) and by the possibility of selecting a simplified menu for entering the most frequently used parameters.
The instrument can also select the parameters is needs to display as a function of the hardware configuration, automatically concealing those that are not influential.
To simplify the configuration even further, a programming kit is available for PC, which includes a menu driven configuration program for Windows and the necessary cable to connect the instrument (see data sheet cod.80021).
The programmer, as well as executing the program controlling the main output (heat/cool with two independent PID loops), can also retransmit 2 different setpoint profiles, with a common time base, to a slave controller using the two analogue outputs.
In the execution phase of the programmer, the two displays are used to monitor the behaviour of the program and make any necessary adjustments immediately.