• Monitoring outputs
• Start button
• Feedback loop
• Unicode or multicode evaluation units
• Guard lock monitoring

CES evaluation units combine transponder evaluation and a safety relay in one device

The CES evaluation units have two enable paths and monitoring outputs for each read head connected. Depending on the series, the devices have additional monitoring outputs as well as connections for a monitored Start button and feedback loop.

Start button

Evaluation units with a connection for a Start button permit a monitored, manual start. The relay is started by actuating a button. The button is monitored for jamming or possible tampering (monitoring of the falling edge). Prior to starting the evaluation unit, the safe state of the safety components connected must be re-established.

Feedback loop

Components connected downstream of the safety relay can be monitored for correct function. For this purpose normally closed contacts on these components are integrated into the feedback loop on the evaluation unit.

Unicode evaluation units

With the unicode version, the actuators must be taught-in on the evaluation unit. During teach-in the actuator code is assigned to the evaluation unit. This code is saved in the evaluation unit. Whenever an actuator is read, the evaluation unit compares the code just read with the code saved. Only if the two bit patterns are identical, the actuator is recognized and the enable paths are closed. The number of possible teach-in operations is dependent of the evaluation unit used. Only the last actuator taught-in is detected. The unicode principle provides a high level of protection against tampering.

Multicode evaluation units

Unlike systems with unique code detection, with multicode evaluation units a specific actuator code is not requested, instead it is only checked whether the actuator is of a type from EUCHNER that can be detected by the system (multicode detection). There is no exact comparison of the actuator code with the code saved in the evaluation unit. As a result a teach-in operation is not necessary.

Guard lock monitoring with the safety system CES-AZ

In principle a read head with guard locking can be connected to each CES evaluation unit with standard read distance. Evaluation units in the system family CES-AZ-… monitor the guard locking function in accordance with EN 1088. For information on which device combination can be used as guard locking in accordance with EN 1088, please refer to the related product page and the combination tables. Evaluation units in the system family CES-A-… do not provide safe guard lock monitoring.