Driving technology.
Ensuring reliability.
Redefining safety.

Safety Relays with Integrated Diagnostics and LFT

Triple Protection

If there is an emergency situation in a process plant, a quick response is needed. Sirens, warning lights, or active cooling systems must be activated safely in line with the "energized to safe" (ETS) procedure, while motor controls or emergency shut-down valves are switched off according to "deenergized to safe" (DTS). To ensure safe signal transfer, Pepperl+Fuchs is setting a new level of reliability with newly developed safety relays. With triple redundant switching contacts, the interface module from the tried-and-tested K-System provides reliable and safety-related activation and deactivation for applications in accordance with IEC61508 up to SIL 3.


Intelligent safety relays with 1oo3 architecture, diagnosis, and line fault transparency
Certification in accordance with ATEX/IECEx Zone 2 as well as UL
Identical input circuits for all devices from the entire portfolio
Immunity against test pulses from all common control panels


Increased Availability

Increased Availability

The new safety relays are based on a 1oo3 architecture (one-out-of-three) with triple redundant contacts. This ensures reliable switching on or off—even with two faulty contacts. Rely on high availability of the safety functions in your plant!
Minimum Test Effort

Minimum Test Effort

Thanks to the integrated diagnostic function, one of the three contacts is automatically checked during each switching operation. Repeating this process annually means that the interface module will be fully tested after three years with no further testing effort required—so you can benefit from integrated diagnostics of the switching capability.
Continuous Monitoring

Continuous Monitoring

With the line fault transparency (LFT), the safety relays enable constant monitoring of the signal line. Locate possible line faults on the field side and on the controller side without the need for additional wiring.
Unrestricted Compatibility

Unrestricted Compatibility

The safety relays are immune to test pulses from the control panel, which means they no longer trigger unintentional switching processes. In this way, the new interface modules are compatible with all common output cards. You can rely on trouble-free operation in your plant.
1oo3-Architektur in Serie und parallel angeordnet

1oo3 Architecture for Maximum Safety

The 1oo3 architecture—connected in series in DTS applications and in parallel in ETS applications—ensures maximum availability of the safety function after failure of up to two contacts. This provides a safety-relevant advantage compared to force-guided contacts: If a contact on a force-guided relay fails, this can merely be detected and the actuator is not switched on or off. Additional wiring for evaluation channels in the control panel—with the associated effort and costs—is required to feed back information on the position of the switching contact. The new safety relay with 1oo3 architecture thus ensures higher reliability while also featuring easier handling.

Proven in Practice: The K-System

As part of the tried-and-tested K-System, the newly developed safety relays are based on 25 years of know-how and successful application in the process industry. With over 200 isolated barriers for explosion hazardous areas and around 150 signal conditioners for use in safe areas, the K-System offers the widest range of products of this kind for different signal types and applications. It is characterized by cost-effective mounting on the Power Rail, a high level of availability, and ease of maintenance. Removable terminals allow quick exchange of the safety relay in the case of a fault without having to disconnect the wiring. Find the right solution for your specific application!

K-System Safety Relais from Pepperl+Fuchs

Entre em Contato

Do you have questions about the safety relays, or do you want to receive more information? We are happy to help! Simply fill out the contact form to send us a message.