Safety by design
Safety should never be an afterthought when it comes to machine design. Instead of added once the production equipment is in place; preferably safety should be built into every component from the start to reduce risk upfronts. Smarter, connected components with improved processing power and advanced communication capabilities can create more intelligent systems that permits you to reach ongoing safety and productivity.
What should a total safety solution include?
Look for an integrated safety controller that provides safe machines on one platform, through one network and using one software. At the same time, maintaining functional separation between control and safety. Even though there are independent controllers for process and safety control, both should:
- Reside on the same platform
- Share the same core components
- Be programmed with the same software
- Travel on the same network
- Communicate with each other through a shared high-speed data bus that is tightly synchronized and not affected by I/O and network traffic. To avoid unnecessary points of failure, there should be no wiring or gateways between the two controllers
A total safety solution should also include integrated:
- Safe Torque Off (STO) on servos and on inverters, so operators can safely stop the drive without disconnecting the main power, ensuring maximum safety and efficiency.
- Safely-limited speed (SLS) function on inverters that monitors speed, so that the predetermined speed limit is not exceeded
- CNC safety functions including safety signal comparisons, speed monitoring between the command speed and the true speed of the servo and spindle motors and redundant energy stop
- Robot safety functions that limit the speed, range of movement or torque of the robot when safety sensors are activated, allowing robots to operate near people.
Essential safety functions enable collaborative human-machine operation
Bolted on vs Built in
When safety is built-in up-front instead of bolted on after the fact, machines can be designed with safe operation as a basis for streamlined performance and improved safety on and around machines. Functional safety at the machine level that can also tie into the Industrial Internet of Things (IIoT) network and allow for more:
- Can support visualization applications for safer training in hazardous environments
- Even if equipment is from different manufactures, interactive safety that allows maintenance teams to monitor and diagnose events over a single network.
- Provide safe operation without hard-guarding with safety sensor data, machine reaction time and safe motion functions
- The cost of the fully integrated approach is offset by the higher installation and maintenance costs of basic safety components.