Rockwell Automation 442L SafeShield Safety Light Curtain Hardware User Manual
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SafeShield Safety Light Curtain Hardware User Manual
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Figure 9: Example of mechanical protection of fixed or floating blanking
➢ After modifying the blanking, check the protective field with the
test rod. Instructions can be found in the “Daily Functional 
Checks of the Protective Device on page 31.
➢ Also pay attention to the warnings in the related chapter.
Properties of Blanked Areas
• The SafeShield safety light curtain is capable of blanking a total of 
four areas simultaneously.
• Fixed and floating blanking can be mixed.
• A minimum of one beam spacing must exist between two blanked 
areas. The SCD software automatically ensures that this is the 
case during the configuration. Exception: It is not necessary to 
maintain any distance between an area of floating blanking with 
partial object monitoring and an area of fixed blanking without a 
positional tolerance. In this case the effective resolution for the 
overlapping is equal to the sum of the effective resolutions in the 
two areas (see Table 10 and Table 11).
• The first beam of the light curtain (closest to the 7-segment
display) cannot be blanked. It is needed for the synchronization 
between sender and receiver.
• With fixed blanking, the 7-segment display indicates r as soon as
sender and receiver are aligned.
Blanked area, sides 
protected by 
mechanical barriers
Fixed Blanking
Figure 10: Schematic layout of the fixed blanking
The SafeShield safety light curtain is capable of fixed-blanking one 
or several adjacent beams, e.g. to allow continued operation in 
spite of an obstruction such as a table placed permanently in the 
light path.
The blanked area will no longer be part of the protective field. 
Objects to be blanked out must therefore be permanently located 
inside the blanked area (1). As soon as the object is removed from 
the beam path, the light curtain will send a signal to stop the 
dangerous movement (2). Protection is otherwise no longer 
guaranteed.
Notes On devices with a physical resolution of 14mm, you can
set an area positional tolerance for the fixed blanking of 
maximum ±2 beams. This is e.g. helpful when blanking 
vibrating objects. The effective resolution of the light 
curtain does not change due to the positional tolerance.
In addition you can define a size tolerance of –1 beam, i.e. 
the blanked object is allowed to be a maximum of 1 beam 
smaller.
Depending on the size tolerance configured, the effective 
resolution reduces at the edges of the blanked area as per