Muting with AS-Interface – cost-effective, easy, flexible

Using AS-Interface as a bus system, it is possible to implement muting applications up to SIL3/PLe easily and efficiently. Thanks to ASi-5 Safety, you can now realize cross-muting and sequential muting far more cost-effectively than with comparable Ethernet-based solutions. Our new, compact ASi-5 Safety Muting Module processes all signals required for muting. Ready-certified muting modules can be configured quickly and easily.


We also offer a solution for widely dispersed sensors: our active distributors capture the signals where they occur. All of Bihl+Wiedemann's muting solutions allow you to benefit from the proven advantages of ASi: Free choice of topology, extremely easy installation thanks to piercing technology as well as drastically reduced cable use. Find out here why AS-Interface is a resource-saving technology.

What is Muting?

Muting refers to the momentary bypassing of electro-sensitive protective equipment. This could be, for example, a light barrier or light curtain. The distinction between expected materials and unexpected objects or persons is made using corresponding muting sensors. When arranging the muting sensors, a distinction is made between cross-muting and sequential muting. ASi as a bus system makes it possible to easily, efficiently and cost-effectively implement the various muting arrangements. Both muting arrangements can be conveniently parameterized using the PC software.

The arrangement of the two sensors with cross muting is crossed. They must both be activated simultaneously to initiate the muting cycle.

With a sequential arrangement, multiple sensors are connected one after the other; they must be activated or deactivated consecutively in a certain sequence.

Advantages of the ASi-5 Safety Muting Module

cost savings

Benefit from significant cost advantages in comparison to comparable Ethernet-based muting solutions from other providers. Apart from the significantly lower module costs, AS-Interface can also save up to 70% in wiring costs compared to round cable solutions.


All signals in one module. The modules can be connected flexibly, whether for cross-muting or sequential muting. Unused inputs and outputs can be used for other applications. Alternatively to processing the relevant signals in the Safety Monitor, they can also be forwarded via PROFIsafe, CIP Safety, FSoE, or openSAFETY.


Using our Bihl+Wiedemann Software Suite, ready-certified muting devices can be configured quickly and easily for many applications. This way, it is possible to make further setting options, such as "End muting when the light barrier is released," "Tolerated interruption time," "Belt stop" and timing parameters. No complex programming in the control system is required.

Proven ASi

AS-Interface allows you to benefit from freely selectable topology. Thanks to piercing technology, the installation process is extremely simple and fast. This not only saves on material and assembly costs, but also minimizes errors during installation.

One module for all signals

  • Cost-efficient solution for cross-muting and sequential muting with many inputs and outputs
  • All signals required for muting in just one module using one ASi-5 address
  • Convenient parameterization via the PC software with a certified muting building block
  • For example, unassigned inputs and outputs can be used to control muting lamps and motors or to integrate push button modules
  • All relevant signals can be preprocessed in the Safety Monitor or optionally forwarded via PROFIsafe, CIP Safety, FSoE or openSAFETY


View ASi-5 Safety Muting module

Muting with active distributors

When it comes to muting the important thing is to consider the individual requirements in advance. It doesn't always make sense to bring all the signals to one point – for example when the sensors are too distant from each other. Bihl+Wiedemann also offers appropriate solutions for such applications – for example where active splitters are used. These collect the signals where they arise. All required signals can then be integrated via drag & drop in the PC software.

Safe input modules

  • 1 × 2 channel safe input (SIL3, PLe) 
    • OSSDs or
    • Floating contacts

Digital I/O modules

  • 2I/1O module
  • 4I, 4O or 4I/4O module

The active distributors in detail

  • Connection of any sensors and actuators
  • Safety and standard ASi node
  • Make standard sensors and actuators ASi compatible
  • Up to protection class IP67
  • On M12, M8, push-in terminals or connecting wires
  • Round cable length: 0.25 m, 0.6 m, 2 m, 5 m, or according to customer requirements

Installation in cable duct

Compact design optimized for the cable duct, especially suitable for individual installation paths.

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Do you have questions about our Muting solutions?

ASi – A resource-saving technology

Thanks to the greatly reduced wiring effort with AS-Interface, you save assembly and material costs. This saves valuable resources.


More information!