Exi controller CTR 210i (ATEX)
The intrinsically safe process controller CTR 210i is designed for the realisation of complex control functionalities. The CTR 210i can be installed inside the hazardous area, ATEX zone 1, in local control panels or in IP 65 field housings.
Typical applications:
- Temperature control of batch reactors
- For the installation in local control panels in ATEX zone 1
- Using in pilote plant stations or mini plants
- Flow and ratio control in meetering skids
- Auto / manual stations for the local control of actuators
Control functionalities:
- Local setpoint controller
- Remote setpoint controller
- Ratio controller
- Difference controller
- Setpoint setter function
- Auto / manual station
- Double loop controller
- Cascade controller
- Automatic ramp controller
The following inputs and outputs are available:
- Three analogue inputs 4-20 mA or Pt100 (3-wire)
- Two analogue outputs 4-20 mA for the valve control
- Six digital inputs for switch functions
- Six digital outputs for alarms
- Modbus data interface
Typical connection of the CTR 210i:
Intrinsically safe sensors and actuators can be connected at the CTR 210i directly. The intrinsically safe power supply is provided by the power supply module PSC 300i. For the Modbus communication to a supervisory system the interface module IPC 300i is required.

Special functions for the automatisation of batch reactors:
- Splitrange output for the control of heating and cooling valves
- Cascade control function for a product / jacket temperature control
- Two parallel PID controller
- 16-step setpoint programmer function
- Avoiding of temperature overshots in the reactor
- Limitation of the temperature difference between product and jacket
- Dynamic activation of the integral part of the PID
- Switching functions via digital inputs: different parameter sets, security outputs, setpoint ramps, releases, input and setpoint selection
Heating processes without temperatur overshots:
At the temperature control of a batch reactor it’s important to reach the product temperature quickly without temperature overshoots or oszillation around the setpoint.
In this function the master controlle of the cascade controls the product temperature. He works as a proportional controller and the operating point has the same value like his set point.
When the product temperature is rising, the value of the control difference is decreasing and the product- and the jacket temperature meet each other at the required set point.
Dynamic limitatin of the temperature difference:
In the case of cascade control, it's possible to have a dynamic limitation between the product- and the jacket temperature. This prevents chemical reactions of the product at the hot jacket and it prevents the damage of the enamel inside of the reactor.
Automatic setpoint programmer function

It‘s possible to program a set point curve with 16 set point steps and 16 time intervals. It’s also possible to switch the digital outputs during each program step.The start, stop and the reset of the program can be activated in a special user level without going into the program levels.