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  • Programmable user level
  • Setpoint changeover
  • Ramp function
  • Power on delay
  • 2 limit comparators
  • Timer function
  • Self-optimization
  • Service counter
  • RS485 interface optional
  • UL and cUL approvals

The JUMO cTRON Series compact controllers are freely configurable and universally applicable compact controllers in various DIN formats for controlling temperature, pressure and other process variables. The main areas of application are heating cabinets, temperature stabilizing and cooling systems, drying and freezing systems and laboratory furnaces and sterilizers in the food, plastics and packaging industries.

With all models, one red and one green seven-segment LED display are used to display processvalues and parameters. There are a further seven LEDs available to display switch positions, manual mode, ramp function and timer mode. Operation is by four keys on the front panel.

Depending on the hardware configuration, the instruments can be used as 2-state controllers, 3-state controllers, modulating controllers or continuous controllers. Self-optimization, ramp function with adjustable gradients, manual mode, power ON delay, two limit comparators, extensive timer functions and a service counter are included, even in the basic version.

Each instrument has a universal measurement input for an RTD temperature probe, athermocouple and standard signals (current, voltage); linearizations of more than 20 sensors are stored. All types are equipped with at maximum two binary inputs, one logic output and two relay outputs. In addition every type can optionally be delivered with a third relay output or an analog output.

A setup interface is available as standard for configuration with the setup program (option). The instruments can be integrated into a data network (Modbus) via an optional RS485 interface.

Electrical connection is at the rear, via screw terminals (pluggable terminal strips).

Standard features include tried and tested self-optimization (oscillatory method), which makes it possible for the controller to be matched to the control loop by a user who is not a control technology expert. The response of the control loop to specific changes in the manipulating variables is evaluated and the controller parameters of proportional band, reset time, derivative time, cycle time and filter time constant are calculated.

Parameters which are frequently changed by the user can be combined at the specially created user level (in the setup program). The operating level available as a factory setting is then hidden.

Binary functions include:

  • Start/cancel self-optimization
  • Change to manual mode
  • Manual mode locking
  • Controller off/on
  • Hold/cancel/reset ramp
  • Setpoint changeover
  • Keyboard/level inhibit
  • Display off
  • Acknowledge limit comparators
  • Acknowledge timer
  • Start/hold/cancel timer

The binary functions can be combined with one another (in the setup program).

Functions of the outputs:

  • Analog input variable
  • Process value, setpoint
  • Ramp end value, setpoint
  • Output level, controller outputs
  • Timer runtime/time remaining
  • Binary inputs
  • Limit comparators
  • Timer signals
  • Tolerance band signal
  • Ramp end signal
  • Service alarm

The ramp function allows a defined approach of the process value from time t0 to the setpoint SP. The slope is set by a gradient (Kelvin per minute, per hour or per day) at the configuration level. It is active rising or falling, when the setpoint changes. When the supply voltage is switched on, the ramp function starts with the current process value.

Two limit comparators are available, each with eight different switching functions. When an alarm value is exceeded, a signal can be output or an internal controller function initiated. Hereby extensive alarm and limit functions can be realized.

The timer signal can be switched to the binary outputs or processed internally. This allows implementation of time-dependent functions, such as time-limited control or setpoint changeover. In addition, a time can be specified after the timer ends, to output a time-limited signal after the timer has expired or to specify the duration of time-delayed control.

The service counter can monitor the ON period or the switching frequency of a binary signal (of a relay, for example). If a defined limit is exceeded, a signal is generated that can be output at a binary output.

The instrument has a setup interface available as standard. Use this, together with the setup program (accessory) and a setup interface (accessory) to configure the instrument.

The serial interface is used for communication with higher-level (supervisory) systems. The Modbus protocol is used for transmission.

The setup program for configuring the instrument supports several languages (including German, English and French). You can use it to create and edit sets of data and transfer them to the instrument, as well as read them out from it. The data can be stored and printed out. There are additional program modules available to expand the setup program.

The startup function is a component of the setup program and is used to record process variables during startup (max. 24 hours). The charts recorded are available on the PC and can be used to document the system.

Jumo cTRON Controller Software
Setup Program & Start-up software package for cTRON controllers
Jumo PC Interface with USB/TTL Converter