GuardLink®: the safe series connection

GuardLink ™ technology is a security-based communication protocol. In this short article we will talk about how Guardlink® works, the reason for its importance, the features and the benefits it can bring to your business.

Two very important challenges for entrepreneurs are the safe stopping of the machine and the reducing downtime. For this reason the serial connection of safety input devices has become a very popular practice.

The real problems, however, arise in the event of intervention due to breakdowns, blocks and maintenance of the production lines. The lack of up-to-date, accurate and integrated diagnostic information in the safety control system generates an increase in the management times of machine downtime.

With GuardLink ™ technology – Rockwell Automation – it is possible to provide safety and diagnostic information over the same cable. This communication protocol makes it possible to simplify the system and to transmit information to the control system more quickly, allowing a common and safe management of all safety sensors. By connecting to a safety relay and using an EtherNet/IP network interface, information is easily transmitted to the control system to increase the availability of diagnostic data.

The GuardLink® communication protocol requires no configuration and features a daisy chain cabling topology with M12, Plug and Play connectors. It also allows you to connect up to 32 safety input devices in series while maintaining a high level of safety.

ROCKWELL AUTOMATION GuardLink® FEATURES

It allows access to the diagnostic data of each individual actuator
It supports remote locking, status indication, reset and reset of errors in safety input devices
It can be integrated with the Logix 5000 ™ controller platform thanks to the add-on profile in Studio 5000 Logix Designer®
Up to 1000m connection distance (30m between one coupler and another)
It supports the connection of safety devices with electromechanical or solid state safety outputs
It uses the EtherNet/IP ™ 440R-ENETR interface to share diagnostic information over the network
Up to two safety circuits (GuardLink® and EMSS or OSSD devices) can be supported with the Guardmaster® Dual GuardLink® (DG) safety relay

ROCKWELL AUTOMATION GuardLink® BENEFITS

GuardLink® allows you to reduce wiring costs by 20% to 38%. This is for two main reasons:

Small cable size: 4 conductor cables for cascade connection instead of 8-pin cables;
Standard M12 connectors and 5-wire cables to reduce wiring errors and save time during installation.

This safe series connection system cascades safety signals across GuardLink® devices and enables diagnostics on the same cable. Another benefit is remote recovery to speed up machine access and reduce troubleshooting time.

Here there are some examples of Rockwell Automation devices that can be connected to GuardLink® device-level safety connection technology.