Safety standards have strict requirements for muting lamps and safety indicators, which cannot be ignored. Supplemental indication that does not form part of the safety system, but acts as guidance to the operator and other workers, can have a dramatic effect on increasing productivity, as the experts at Turck Banner explain.
(See Turck Banner at MachineBuilding.Live, 2 October 2024, on stand 109)
In regard to machine safety systems, one of the main culprits for production loss is due to operator timing. Operators often alternate between being too quick to anticipate the safe (muted) part of the machine cycle, thereby causing a safety trip, or being too cautious, thus losing time after the safe part of the machine cycle has begun the next operation.
Supplemental indication can help to reduce these problems, but the selection of this extra indication is critical to ensure that productivity is enhanced. If the operator has to change their focus to look for the indicator, time and efficiency will be lost, likewise if the indicator is unclear. The area lighting doesn't have to be white. By changing the colour of the lighting when it is safe to perform the next task, the operator can observe this with their peripheral vision, no time is lost and they are unlikely to jump the gun.
Lighting changes should be restricted to the area that is being monitored, to avoid creating confusion or distractions.
The choice of colours is also important. Changing between red and green to indicate unsafe and safe conditions is often a good choice. However, if the operator is required to perform intricate or complex tasks, using a green light may hinder their ability to see clearly and so a more natural white light would be preferable to indicate the safe condition.
If a process has long periods between safe conditions, the addition of an amber period prior to the safe time could assist the operator in preparing for the next task, especially if the operator has to manage multiple machines. Conversely, for a process with a short cycle time, the addition of an amber period may actually hinder the operation by creating a situation where the operator may be more likely to act prematurely.
In the context of machine safety systems, the psychological effects of lighting are particularly significant. Workers operating heavy machinery, or performing intricate tasks, require focus and attention to detail. Appropriate lighting not only helps them see clearly but also contributes to a sense of security and confidence in their work environment. When workers feel safe and comfortable, they are better equipped to perform their duties effectively, ultimately driving productivity levels higher.
Another area where production is lost due to safety systems is in locating the cause of a safety activation. Sometimes the cause is obvious, if for example the operator has been too eager and tripped a safety light curtain. Other activations may be less obvious and much more difficult to diagnose, for example when a door sags on its hinges and the safety device monitoring the door becomes misaligned. In these conditions choosing a safety system with good diagnostics can save a lot of time and stress in resuming production.
Turck Banner have both lighting products and safety systems ideally suited to industrial environments. Their LED lighting and indication range includes products with IP65 and IP69K ratings, that are also resistant to harsh chemicals and cutting fluids, which allow them to be mounted close to where the light is required. They provide bright and uniform illumination which can change colour by either hard-wired connection or PLC protocols.
Turck Banner's safety portfolio includes illuminated E-Stops where the whole base turns red if the button is pressed, and safety controllers with in-series diagnostics, which pinpoint the location of the safety device that has been activated, as well as providing device monitoring to provide early warning of common problems like misalignment.
Compact safety solutions
Turck Banner's new compact safety solutions offer a simple way to configure extra lighting functionality to enhance productivity.
The IP65/IP67 safe I/O modules with Profinet/ Profisafe and EtherNet/IP/CIP Safety, allows Turck Banner to provide a solution for every application scenario: full-safety I/O modules with eight safe inputs/outputs or hybrid I/O modules in which standard and safe inputs/outputs are combined in one device. All modules work independently, or in conjunction with external safety PLCs and controllers. The safety configurator allows the device to work as an independent IP67 safety controller, processing safety signals and IO-Link function in a single device.
Turck Banner says the compact hybrid controller is unique in that one half of the module has safety connections, while the other side has non-safety connections. Combining the two halves enables the user to analyse in-series safety devices by providing in-series diagnostics via IO-Link. The device also allows the user to control the supplemental indication and lighting via IO-Link or standard I/O ports.
Productivity and lighting are intertwined components of machinery safety systems. Intelligent lighting enhances visibility, imparts essential information, promotes safety, and fosters a conducive work environment, all of which contribute to improved productivity. By combining this with decentralised safety I/O modules that can be mounted directly on the machine without an enclosure, machine safety has become much easier and colourful.