Banner EZ-SCREEN­ Safety Light Curtain Systems - Manual (Page 24)

page 24
Banner Engineering Corp. • Minneapolis, MN U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
Installation and Alignment
EZ-SCREEN Grid
Instruction Manual
WARNING . . .
Avoid Retroreflective
Installation
Do not install emitters and
receivers in “retroreflective”
mode, with less than a 45° angle
of incidence, as shown in
Figure 3-7.
Sensing could be unreliable in this
configuration; serious bodily injury
or death could result.
!
3.3.5 Use of Corner Mirrors
EZ-SCREEN Grid Systems may be used with one or more vertical corner mirrors
in perimeter-guarding applications (see Section 2.2 for availability). The use of
corner mirrors reduces the maximum specified emitter/receiver separation by
approximately 8 percent per mirror (see Section 3.4).
Mirrors are not allowed for applications that would allow personnel undetected
access into the safeguarded area.
If mirrors are used, the difference between the angle of incidence from the
emitter to the mirror and from the mirror to the receiver must be between 45°
and 120° (see Figure 3-7). If placed at a sharper angle, as shown in the example,
an object in the light grid may deflect beam(s) to the receiver, preventing the
object from being detected (i.e., “false proxing”). Angles greater than 120° result
in difficult alignment and possible optical short circuits.
Figure 3-7. Positioning of corner mirrors
45°< A < 120°
Emitter
Mirror
Receiver
A