Banner EZ-SCREEN­ Safety Light Curtain Systems - Manual (Page 7)

page 7
Banner Engineering Corp. • Minneapolis, MN U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
System Introduction
EZ-SCREEN Grid
Instruction Manual
Pass-through hazards: Perimeter- and access-guarding applications must be
designed to prevent pass-through hazards. A pass-through hazard occurs when
an individual is allowed to cross the safeguard (which issues a stop command to
remove the hazard). Subsequently, the person may cross into the hazardous area
but their presence is no longer detected. A danger arises because the machine’s
dangerous motion may resume while personnel are within the safeguarded area.
Several measures can be taken to prevent a pass-through hazard, which include,
but are not limited to:
• A latching output on the safety light grid guarding the access or perimeter to
the hazardous area, which requires a manual reset procedure before machine
motion can be re-initiated. The reset switch has several requirements,
including its placement outside of the guarded area, and out of reach of
anyone inside the guarded area. In addition, the reset switch operator must
have full view of the entire guarded area during the reset procedure.
• Supplemental safeguarding, such as described by the ANSI B11 series of
safety requirements or other appropriate standards, to prevent personnel
from standing undetected within the guarded area.
In addition, hard guarding should be installed around the hazardous area to
prevent personnel from entering the guarded area, undetected by the safety light
grid, or other safeguarding means.
Because the EZ-SCREEN Grid has a selectable (latch or trip) output, it must be
installed and configured to prevent hazardous motion from occurring while
personnel are within the guarded area. See Section 4.1 for more information.
EZ-SCREEN Grid may be used to guard many types of machines, including
those for packaging, palletizers, roll formers and many types of work cells,
including robot cells. The guarded machine(s) must be capable of stopping at
any point in their motion; see page 2 for a complete list of requirements for
machines that may be guarded by this system.
WARNING . . .
Use of Trip Output
Application of power
to the EZ-SCREEN
Grid System MUST NOT initiate
dangerous machine motion.
Machine control circuitry must be
designed so that one or more
initiation devices must be engaged
(i.e. a conscious act) to start the
machine in addition to the EZ-
SCREEN Grid System going into
RUN mode.
Failure to follow these instructions
could result in serious bodily
injury or death.
!
CAUTION . . .
Other Applications
For applications not
covered in this manual, contact
a factory applications engineer
before installing or using the EZ-
SCREEN System.
!
Figure 1-4. EZ-SCREEN access-guarding application
Emitter
Receiver
Hard Guarding Hard Guarding
Hard Guarding