Orateur
Description
Configuring hardware safety interlocks at synchrotron facilities has traditionally required PLC
expertise, custom ladder logic programming, and specialist support --- creating bottlenecks that
slow scientific operations. We present \textbf{WAGO Interlock}, an open-source tool jointly
developed by the Advanced Light Source (ALS, Lawrence Berkeley National Laboratory) and the
European Synchrotron Radiation Facility (ESRF), designed to eliminate that barrier entirely.
The system leverages cost-effective WAGO 750-series modular hardware (\textasciitilde\$1,700/unit,
versus \$4,000+ for comparable Allen-Bradley systems) paired with an intuitive web interface and
command-line tool. Scientists and operators can define complex interlock logic --- covering
thermocouples, analog/digital I/O, relays, and valves --- in minutes, without writing a single
line of code. Configuration is driven by a human-readable YAML file and a role-based permission
model (\texttt{Master}/\texttt{Admin}/\texttt{User}) that enforces controlled access across
multiple facilities and beamlines. A built-in change tracker, live signal monitoring, and
real-time plotting make the system audit-ready from day one.
The hardware platform has been proven at scale at the ESRF, with over 400 WAGO units deployed
across all beamlines for more than 20 years, covering use cases including laser safety interlocks,
thermal protection of beamline optics, vacuum integrity, collision prevention on motorized stages,
and sample annealing protection.
This contribution introduces the new EPICS IOC integration, which enables full interlock
management through Phoebus/CS-Studio OPI panels, a web browser interface, an interactive CLI,
and a Podman-containerized deployment --- fitting seamlessly into any standard EPICS control
system environment. Response times measured on the current implementation are below 20\,ns for
digital inputs and below 80\,ms for analog inputs, operating with multiple concurrent interlock
instances. The EPICS IOC, web application, and CLI are all available as open-source software
hosted jointly on the ESRF GitLab and ALS internal repositories.
With 20 units (10 large, 10 small) scheduled for deployment across ALS beamlines and laboratories
before September 2026, WAGO Interlock is production-ready and open to collaboration and feature
contributions from the broader EPICS community.