4.4.2
Overview and general description
Muting is an automated process that temporarily bypasses safety functions of a control
system or protective equipment. Muting allows certain objects (e.g., pallets loaded
with material) to pass through electro-sensitive protective equipment (ESPE) such as
a safety light curtain and into a hazardous area. During this transport operation, the
Muting function bypasses monitoring by the electro-sensitive protective equipment.
Three different function blocks are available for muting:
•
Parallel muting
A1
B1
A2
B2
Figure 9: Muting with two sensor pairs arranged in parallel (A1 / A2 and B1 / B2)
•
Sequential muting
A1
B1
A2
B2
Figure 10: Muting with two sensor pairs arranged in sequence (A1 / A2 and B1 / B2)
•
Cross muting
A1
A2
Figure 11: Muting with a sensor pair arranged crosswise (A1 / A2)
Muting sensors
Muting sensors monitor the presence of the material while it is being transported. Care‐
ful selection of the sensor type and how the sensors are arranged makes it possible to
distinguish between objects and people.
In conjunction with the muting sensors and the electro-sensitive protective device, the
object that is being transported generates a precisely defined signal sequence while it
is traveling into the hazardous area. The muting sensors must ensure that all dangers
are eliminated in the event of someone entering the area protected by the electro-sen‐
PROJECT PLANNING
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8024589/2020-11-10 | SICK
O P E R A T I N G I N S T R U C T I O N S | Flexi Compact
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Subject to change without notice