Medium-duty safety switches

Medium Duty Safety Switches for Machinery and Industrial Equipment

What are medium duty safety switches?

Medium duty safety switches are interlock devices designed for machines and production equipment where reliable access protection is required, but where the environment is not as demanding as heavy industrial applications. They combine compact size with durable mechanical performance and are ideal for production lines, packaging systems, assembly cells and intralogistics. Compared to heavy duty switches, medium duty solutions are lighter, easier to install and easier to maintain, while still meeting functional safety requirements.

How do medium duty safety interlock switches work?

Medium duty interlocks monitor the status of machine guards, such as doors, hatches or covers. When a guard is opened, the switch sends a stop signal to the safety controller to safely remove power or stop hazardous motion. Versions with guard locking keep the guard locked until the machine has reached a safe stop. Depending on the configuration, these switches achieve safety levels up to PLd or SIL2.

Where are medium duty interlock switches used?

These safety switches are used in applications where moderate mechanical stress is expected, such as packaging lines, sorting machines, small robots, semi-automated workstations and light-duty conveyors. Their compact form makes them easy to integrate into aluminium profiles, small enclosures and modular machine frames. OEM manufacturers benefit from standardisation and reduced installation time.

Safety standards: PLd, SIL2 and EN/ISO requirements

Medium duty safety switches comply with international machine safety standards such as EN ISO 13849 and EN 62061. Depending on the selected modules, they can achieve PLd or SIL2, making them suitable for applications with medium-level risk, including fast-moving parts, small process installations or equipment with short run-down times.

Modular medium duty interlock systems

Modular configurations and available function modules

A key benefit of medium duty switches is their modular design. Users can select from a wide range of modules—such as guard locking, access request buttons, emergency stops, key modules, indicator LEDs and push buttons—and combine them into a single compact housing. This reduces wiring, installation time and required space.

Advantages of modular safety interlock systems

Modularity makes these switches suitable for both new installations and retrofit projects. Fewer mounting points and reduced cabling improve reliability and simplify maintenance. The modular approach also allows precise tailoring of functions to each access point, which is highly beneficial for OEM machine builders.

tGard medium duty safety switches from Fortress Safety

Why choose tGard interlock switches?

The tGard series from Fortress Safety is one of the most widely used medium duty interlock platforms. tGard combines multiple electrical and mechanical functions in a single metal housing. It is IP65-rated, built for long service life and designed for straightforward installation.

tGard modules: guard locking, E-stop, LEDs and key modules

The tGard platform supports a wide range of modules, including:

• Guard locking (magnetic or solenoid locking)
• Emergency stop (E-stop)
• Push buttons and illuminated indicators
• Key switches and personal safety key modules
• Request-to-enter buttons and reset functions

This flexibility allows machine builders to create a customised interlock solution using a single product family.

Applications for medium duty safety switches

Integration in packaging, robotics, assembly and logistics

Medium duty interlocks are commonly used for guarding access points on packaging lines, compact robotic systems, assembly workstations and material handling equipment. They improve both operator safety and process efficiency.

Use in compact machines, profile systems and OEM designs

Thanks to their small footprint, medium duty switches integrate well into aluminium profile systems, modular frames, machine enclosures and OEM machinery with limited space.

Medium duty vs heavy duty safety switches

Key differences in strength, lifespan and environments

Heavy duty switches are built for high forces, shock loads and contamination. Medium duty switches are intended for lower mechanical stress and provide a lighter, more cost-effective solution. They are easier to install and maintain and are ideal for standard industrial environments.

When to choose medium duty instead of heavy duty

Medium duty switches are the best choice when space is limited, mechanical loading is moderate or when cost-efficiency is required. For demanding applications such as presses, heavy conveyors or high-force processes, heavy duty switches remain the correct solution.

Safety keys and escape release options

When are safety keys required?

Safety keys are essential in applications where operators may enter the machine area. They ensure the machine cannot restart while someone is inside the hazardous zone.

Escape release for full-body access applications

For full-body access guards, escape release is mandatory. The tGard platform includes mechanical modules that allow emergency escape from inside the safeguarded area.

Common selection mistakes and how to avoid them

Incorrect choice for run-down time applications

A common mistake is selecting a non-locking switch for machinery with run-down time, which can result in exposure to hazardous motion.

Missing escape release on full-body access points

Failing to include escape release in large machines or robot cells can create serious entrapment risks.

Selecting the wrong IP rating or hygiene level

Environmental conditions such as washdown, dust or chemical cleaning often require higher IP ratings or hygienic designs.

Engineering support and installation assistance

Whether you need a single switch or a complete multi-access system, we support you from risk assessment to commissioning. We provide engineering advice, installation support, technical d