CIP Safety

CIP Safety is a functional safety communication protocol that extends the Common Industrial Protocol (CIP). It lets safety controllers, safety I/O blocks, interlock switches, light curtains, drives, and other safety devices communicate with standard devices on the same industrial network. It is certified by TÜV Rheinland as a black channel protocol and supports applications up to SIL 3 according to IEC 61508.

Source checked3/3 values · 2026-10-25

Specification

1 source

Transports	ethernet l2, other
Architecture	producer consumer
Encoding	binary

Study notes

CIP Safety extends CIP by adding safety application-layer services and diagnostics.
CIP Safety supports EtherNet/IP and DeviceNet communication between safety controllers, safety I/O blocks, interlock switches, light curtains, drives, and other safety devices.
CIP Safety uses timestamps to mark the age of produced data and a production identifier so each received message arrives at the correct consumer.
All safety transfers use Safety CRCs or checksums; data and CRC redundancy provide additional protection against corruption.
CIP Safety packets can contain data, timestamp, time correction, and time coordination sections; no packet has all four sections.
The Safety Network Number identifies each network path individually so each device can be uniquely identified.
CIP Safety can coexist with CIP Motion and CIP Security.
The CIP Safety protocol is present only in safety controllers and field devices, which prevents standard devices from posing as safety devices.

Safety

CIP Safety is certified by TÜV Rheinland as a black channel protocol; safety integrity is not dependent on the physical media.
CIP Safety supports SIL 2 for moderate-risk applications and SIL 3 for critical applications according to IEC 61508.
CIP Safety supports products based on ISO 13849 PLd-Cat3 (~SIL2).
CIP Safety mechanisms detect errors and place devices into a safe state when necessary.
Configuration ownership can be enforced to ensure safety configurations cannot be changed by other devices on the network.
The protocol is present only in safety controllers and field devices, which prevents standard devices from posing as safety devices.