Boost Workplace Safety with Non-Contact Sensors & Locks

An brief overview of safety sensors & switches

January.10 2025 | Blog Post, Venus Automation

In today’s industrial settings, ensuring workplace safety is paramount. Safety sensors and switches provide intelligent, reliable solutions to protect workers and equipment. These devices are fundamental in preventing accidents, enhancing operational efficiency, and maintaining compliance with safety standards, making them indispensable in modern workplace protection systems.

Safety Sensors: Precision in Hazard Detection

Safety sensors are designed to detect and mitigate risks before they escalate, enabling a proactive approach to workplace safety. Inductive proximity sensors, for example, monitor the presence of metallic objects near machinery, ensuring smooth and hazard-free operations. These sensors eliminate physical contact, reducing wear and prolonging the lifespan of critical equipment.

For applications requiring advanced security, RFID-encoded Safety Switches can provide dynamic monitoring of guard positions, with capability for high levels of tamper protection. These sensors ensure protective barriers are properly engaged and immediately alert operators to unauthorized access or unsafe conditions. Additionally, stainless steel-bodied safety sensors are tailored for environments with extreme conditions, such as exposure to moisture, chemicals, or high temperatures, delivering consistent performance across a wide range of industries. Magnetic coded sensors add another layer of versatility, particularly in areas where precise positioning and alignment of machine guards are critical. These sensors operate without physical contact and can detect whether guards or doors are fully closed, helping to prevent inadvertent access to dangerous zones. Their robust design ensures reliability in demanding industrial environments.

Safety Switches: Reliable Access Control and Emergency Stops

Safety switches complement sensors by providing manual control over access points and machinery. They are critical for securing hazardous areas and ensuring that operations are conducted only when conditions are safe. Basic manually controlled variants include Safety Enabling switches and Safety Foot Pedal switches, which while being part of a normal operator control are appropriately safety rated for extreme reliability. Limit Switches can also act as monitoring to determine position of moving machine or guard elements.

Additionally, safety switches with interlocking are commonly used to lock guards or enclosures during machine operations. These switches prevent accidental access to dangerous areas until it is safe to proceed, safeguarding both workers and equipment. And of course, the irreplaceable emergency stop is a form of safety switch, offering a rapid and reliable method to halt operations, allowing minimization of further injuries or damage following any incident noticed by workers.

These devices are built to withstand demanding industrial environments, offering durability and tamper-proof functionality. Their reliability underpins their role as a cornerstone of workplace safety systems.

Output & Monitoring

For safety sensors and switches to provide an adequate level of safety for a machine, these inputs must be appropriately monitored with safety-rated responses and outputs. For the core of this system, Safety PLCs or Safety Relays are generally used. Safety PLCs allow custom safety logic, with flexible input/output terminal assignments, but at a comparatively higher cost. Venus Automation offers a variety of models, including the MOSAIC PLC from ReeR, Samos PLC from Wieland, and GEMNIS PLC from Pizzato—each delivering advanced and reliable safety functionality.

Conversely, safety relays lack programmability but have significantly lower costs. Specialised options such as standalone relays, time-delay relays, speed-monitoring relays, standstill monitoring and timer relays, PCB relays and relay expansion modules are available. Additionally, input type-specific control relays are offered, such as the emergency stop relay, safety edge relay, light curtains relay, or two-hand control relay. These options provide effective and application-specific safety responses, and can integrate other inputs such as the safety encoder.

Finally, it should be noted that irrespective of which monitoring system is used, it is the responsibility of the safety contactors or pneumatic safety valves to ensure that the machine reliably stops following detection of a hazard and outputting of the stop command, so it is important that these are appropriately safety-rated.