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2
Introduction
2.1 Features
• An optoelectronic safeguarding device
• Creates a screen of synchronized, modulated infrared sensing beams. Choose from
10 sizes, in 150 mm (6 in) increments:
defined
areas from 150 mm to 1.8 m (6 in to
71 in)
• Compact package for smaller
production
machines
• Models available with Trip or Latch output
operation
(automatic
or manual start/
restart)
• 30 mm (1.18 in)
resolution
• Remote Test input terminals for
simulating
a "blocked"
condition
•
Operating
range up to 15 m (50
ft)
• Type 2 per IEC 61496-1/-2; Category 2 PLc per EN ISO 13849-1
• FMEA tested according to IEC 61496-1, Type 2 requirements
• Receiver LEDs provide system status and
emitter/receiver
alignment
indications
• Highly immune to EMI, RFI, ambient light, weld
flash,
and strobe light
• Two-piece design
•
Vibration-tolerant,
factory burned-in
emitter
and receiver circuitry for toughness
and dependability
2.2 System
Description
Note: This manual refers to an
emitter
and its receiver, and their cabling as "a System".
Banner EZ-SCREEN Type 2
emitters
and receivers provide a redundant, microprocessor-controlled, opposed-mode optoelectronic
"curtain of light", or "light screen". EZ-SCREEN Type 2 typically is used for
point-of-operation
safeguarding, and is suited to safeguard a
variety of lower-risk machinery.
The EZ-SCREEN Type 2 is a two-piece (two-box) system comprising an
emitter
and a receiver, but no external controller. The external
device monitoring (EDM)
function
ensures the fault
detection
capability required by EN ISO 13849-1 Category 2.
The EZ-SCREEN Type 2
emitters
have a row of synchronized modulated infrared (invisible)
light-emitting
diodes (LEDs) in a compact
metal housing. Receivers have a corresponding row of synchronized photodetectors. The light screen created by the
emitter
and
receiver is called the
defined
area; its width and height are determined by the length of the sensor pair and the distance between them.
The maximum range is 15 m (50
ft),
which decreases if corner mirrors are used.
Resolution
is 30 mm (1.18 in).
Both
emitter
and receiver feature LEDs to provide
continuous
indication
of the System’s
operating
status, alignment and error
conditions.
In typical
operation,
if any part of an operator’s body (or any opaque object) of more than a pre-determined cross
section
is detected,
the solid-state Output Signal Switching Device (OSSD) safety outputs turn OFF. These safety outputs are connected to the guarded
machine’s Final Switching Devices (FSDs) that control the machine primary control elements (MPCEs), which immediately stop the
motion
of the guarded machine.
Both OSSD outputs must be connected to the machine control so that the machine’s safety-related control system interrupts the circuit
or power to the MPCEs (Machine Primary Control Elements),
resulting
in a non-hazardous
condition.
Each OSSD is capable of sourcing
0.5A at +24V dc.
The OSSD safety outputs are not capable of performing a “handshake”
communication
with the Muteable Safety Stop Interface (MSSI)
or Universal Safety Stop Interface (USSI) found on other Banner Engineering safety products.
EZ-SCREEN Type 2 is extensively FMEA (Failure Mode and
Effects
Analysis) tested to IEC 61496-1/-2 requirements. The design of the EZ-
SCREEN Type 2 has considered all single faults such that a loss of a
critical
safety
function
will result in a stop command and a lockout
condition.
In the event of an
accumulation
of undetected faults, a remote external test (or check) is required to maintain the safety
function.
EZ-SCREEN
®
Type 2 Light Screen
6
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