10
Rockwell Automation Publication 445L-IN005A-EN-P - May 2018
GuardShield Micro 400 Safety Light Curtains
is blinking, the amount of light is not sufficient for stable operation. After
realigning the light curtain, the protective field must be briefly
interrupted. After removing the object from the protective field, a green
LED indicates a sufficient intensity level.
Adjust and mount the receiver at the center of this operating angle.
After aligning the receiver, rotate the transmitter to find the
transmitting angle. During rotation, the green LED indicates the
transmitting angle of the GuardShield Micro 400 light curtain.
Adjust and mount the transmitter at the center of this operating angle.
Test the protective function of the GuardShield Micro 400 light curtain by
using the test rod, according to
Figure 19 on page 16
.
The insertion of
this rod into the protective field at any position has to lead to a protective
field interruption (illumination of the red LED in the GuardShield
Micr
o 4
00).
Cycle power to confirm that the system powers up and goes to the ON
state.
Figure 10 - Layout of the Transmitter/Receiver
Multiple GuardShield Micro 400 Light Curtains
When two or more GuardShield Micro 400 light curtains are mounted
close to one another, it can be possible for the receiver of one
GuardShield Micro 400 pair to receive infrared light from the
transmitter of another GuardShield Micro 400 pair.
There are various techniques to help prevent or reduce the possibility of
optical interference from light curtains that are mounted in the same
plane. The simplest method is to alternate transmitter and receiver pairs
so that the receiver from a second pair is facing away from the
transmitter of another light curtain pair nearby. It is also possible to
place a physical barrier between pairs to help prevent the infrared light
from reaching another light curtain pair.
Figure 11 - Multiple GuardShield Micro 400 Alignment Options
Cascaded GuardShield Micro 400
Configuration of Operating Modes in Cascading Systems
The operating modes of a cascaded GuardShield Micro 400 can be
configured at the MSR42 control unit.
Two Segment Cascading GuardShield Systems
Operators must not step between the protective field and hazardous
machine parts (bypass prevention), see
Figure 7 on page 9
.
There are a few methods of detecting the presence of a person who
could be standing in front of the machine hazard but inside of the light
curtain. The most cost-effective solution is to interconnect an
additional light curtain in series to the vertical pair (see
Figure 12
). This
solution is accomplished with a cascading pair of GuardShield Micro
400 safety light curtains with a protective height and resolution, which
are based on the risk assessment. It is then necessary to select the
horizontal protected height of the pair of GuardShield Micro 400 light
curtains. This pair provides detection from the vertical pair to the front
of the machine hazard. In most cases, this horizontal pair of
GuardShield Micro 400 can be 30 mm (1.18 in.) resolution as their
purpose is to detect the presence of a person, not fingers.
The next step is to select the interconnect patchcords for the transmitter
and receiver. These patchcords are offered in various lengths (see
Table 5
on page 12
). The final cascading segment, which is not connected to
another pair of GuardShield Micro 400 light curtains is a standard
GuardShield Micro 400 light curtain.
“L-shaped” two segment GuardShield Micro 400 cascading systems
offer protection when it is possible to stand between the vertical light
curtain and the machine hazard (see
Figure 7 on page 9
and
Figure 12
on page 11
).
Transmitt
er
Rec
eiv
er
Transmitt
er
Rec
eiv
er
Incorrect
Correct
Transmitters emit in opposite
direction. Each receiver receives only
the beams of the appropriate
transmitter.
Transmitters emit in same direction:
Optical (physical) barrier necessary
Positioning of the light curtain:
Transmitters emit in opposite
direction.