Rockwell Automation Publication 450L-UM001F-EN-P - March 2022
37
Chapter 4 Safety Function
The muting functionality does not have an impact on the response time of the
450L-E or 450L PAC safety light curtain.
Two-sensor T-type Muting
The sensors and light curtain form the shape of an upside down “T,” when
viewed from the side. The muting sensors (MS) are mounted to form an “X”
sensing pattern where the sensing beams cross near the center of the light
curtain (LC).
Figure 16 - Two-sensor T-type Muting Arrangement
The muting sensors can be mounted symmetrically (equal distance from the
light curtain) or asymmetrically (unequal distance from the light curtain).
The material can break either MS1 first (or MS2 first), then the other sensor,
and then the light curtain. As the material clears the light curtain, it must then
clear MS2 (or MS1) first and then the other sensor. The muting lamp turns on
shortly after the second sensor is blocked, and the light curtain is muted.
Either of these two patterns is acceptable:
•
MS1
↑
MS2
↓
LC
↓
LC
↑
MS2
↑
MS1
↑
•
MS2
↓
MS1
↑
LC
↓
LC
↑
MS1
↑
MS2
↑
The crossing point of the two light beams is situated behind the sensing field
of the safety light curtain in the direction of the dangerous area.
The height of the crossing point of the two muting sensors is at the same level
as or higher than the lowest beam of the light curtain.
Verify that the distance from the crossing point to the protective field of the
safety light curtain is as short as possible.
During the muting process, it is not possible for a person to enter the
undetected dangerous area to the left or right of the object.
With proper arrangement of the sensors, the conveyor can move in the
forward or reverse direction, while also maintaining safeguard integrity.
For connecting the sensors, see
for
the cascading plug-in.
MS
MS
LC
Machine
Material
Material
Conveyor
Muting Lamp
