PTIO sensor terminal blocks and actuator terminal blocks

Sensor terminal blocks and actuator terminal blocks for clear signal wiring

Thanks to their compact design, the PTIO sensor/actuator terminal blocks are tailored to the wiring of modern machine control systems. The sensor/actuator terminal blocks enable you to wire bipolar initiators and actuators with a terminal width of just 3.5 mm. In addition, you are able to wire the terminal blocks with 3- or 4-conductor sensors and actuators.

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  • A wide range of products with versions with PE function or LED display
  • Space-saving due to versions for bipolar initiators and actuators
  • Optimum overview of signal connections with a variety of marking options
  • Modular extension up to a maximum of 50 positions
  • Identical in shape to the feed-in terminals
The initiator terminal blocks with Push-in connection

The initiator terminal blocks with Push-in connection

Color coding in accordance with EN 60947-5-2

The standard version of the initiator terminal blocks with Push-in connection feature orange push buttons on both signal levels. To identify the signal levels more easily, versions are also available with black and white push buttons. The black-white versions of the terminal block conform to EN 60947-5-2. According to this standard, such color coding is provided to differentiate between N/C contacts and N/O contacts in sensor wiring.

Initiator/actuator terminal blocks

Initiator/actuator terminal blocks

Difference between two-, three-, and four-conductor sensors

The Phoenix Contact initiator/actuator terminal blocks enable the easy and compact connection of three- and four-conductor sensors. But why do I need three- or four-conductor sensors?
There are various connection options in sensor/actuator cabling. A specific level of accuracy is required depending on what the sensor is supposed to measure. The two-conductor initiator is the simplest and least accurate type of sensor. With a two-conductor connection, the measurement result is affected entirely by the supply line resistance. This affects the measurement results of the sensors. The use of three-conductor initiator terminal blocks allows three-conductor sensors to be cabled. Due to an additional measuring circuit, these initiators counteract the temperature influences of the supply lines. The connection of four-conductor sensors is an even more accurate solution. The resulting two additional measuring circuits counteract not only the temperature influences, but also the supply line resistances.

Bipolar sensors

Bipolar sensors

Bipolar sensors

The difference between monopolar and bipolar initiators is the number of signal lines. Bipolar sensors have two signal lines, and can therefore receive and forward two different switching signals. An example of such an initiator is an ultrasonic sensor which is used to take distance measurements and to measure objects. Here, the distance to the respective object is determined via the first signal line, while the second signal line is used to determine the dimensions of the respective object. Sensor/actuator terminal blocks for bipolar sensors are a highly efficient solution for this type of sensor, because they can be wired in a very tight space. The sensor terminal blocks for bipolar sensors have a terminal block width of 3.5 mm and feature two signal line inputs and outputs.

Operating the clipx ENGINEER engineering software on a tablet screen

Efficient planning with clipx ENGINEER

Engineering software​ for control cabinet building

The clipx ENGINEER engineering software makes it possible to plan and procure terminal strips, assembled mounting plates, and junction boxes more efficiently than ever, and to seamlessly transfer the data to production – at every workplace. Accelerate your planning process with smart interfaces to your CAE program and to Phoenix Contact applications and configurators.

Open product brochure for terminal blocks

Terminal blocks product brochure


Would you like to get printed information about our sensor/actuator terminal blocks? Below you will find a product brochure on terminal blocks and a brochure on quality tests for terminal blocks.