Overview, Glossary – Banner EZ-SCREEN Low-Profile Safety Light Curtain Systems User Manual
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P/N 133487
Banner Engineering Corp.
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Minneapolis, U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
Overview
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P/N 140044 rev.
E
Banner Engineering Corp.
•
Minneapolis, U.S.A.
www.bannerengineering.com • Tel: 763.544.3164
EZ-SCREEN LP
Instruction Manual
Glossary
PSDI (Presence-Sensing Device Initiation): An application
in which a presence-sensing device is used to actually start
the cycle of a machine. In a typical situation, an operator
manually positions a part in the machine for the operation.
When the operator moves out of the danger area, the presence-
sensing device starts the machine (no start switch is used).
The machine cycle runs to completion, and the operator can
then insert a new part and start another cycle. The presence-
sensing device continually guards the machine. Single-break
mode is used when the part is automatically ejected after the
machine operation. Double-break mode is used when the part
is both inserted (to begin the operation) and removed (after
the operation) by the operator. PSDI is commonly confused
with “Trip Initiate”. PSDI is defined in OSHA CFR1910.217.
Banner safety light screens may not be used as PSDI devices
on mechanical power presses, per OSHA regulation 29 CFR
1910.217.
Qualified Person: An individual who, by possession of a
recognized degree or certificate of professional training, or by
extensive knowledge, training, and experience, has successfully
demonstrated the ability to solve problems relating to the subject
matter and work. (See Designated Person.)
Receiver: The light-receiving component of a safety light
screen, consisting of a row of synchronized phototransistors.
The receiver, together with the emitter (placed opposite), creates
a “screen of light” called the defined area.
Reduced Resolution: A feature that allows a safety light
screen to be configured to produce one or more intentionally
disabled light beam(s) within the light screen, which increases
the minimum object sensitivity. The disabled beam(s) appears
to move up and down (“float”) in order to allow the feeding of
an object through the defined area at any point without tripping
the safety outputs (e.g., OSSDs) and causing a Trip or Latch
condition. Sometimes called “
Floating Blanking.”
Reset: The use of a manually operated switch to restore
the safety outputs to the ON state from a lockout or a Latch
condition.
Resolution: See
Minimum Object Sensitivity.
Safety Distance: The minimum distance required to allow the
machine’s hazardous motion to stop completely, before a hand
(or other object) can reach the nearest hazard point. Measured
from the midpoint of the defined area to the nearest hazard
point. Factors that influence minimum safety distance include
the machine stop time, the light screen system response time,
and the light screen minimum object detection size. Also known
as “Minimum Distance” (EN and ISO) and “Separation Distance”.
Self-Checking (Circuitry): A circuit with the capability to
electronically verify that all of its own critical circuit components,
along with their redundant backups, are operating properly.
Banner safety light screens and safety modules are self-checking.
Specified Test Piece: An opaque object of sufficient size used
to block a light beam to test the operation of a safety light screen
system. When inserted into any part of the defined area, it will
place a system into a Trip or Latch condition. Banner supplies
specified test pieces with each system. See also Minimum Object
Sensitivity.
Start/restart (interlock): When applied to the function of a safety
or safeguarding device, this term refers to the ability of the device
to prevent or allow the machine operating cycle to begin or
resume by normal actuating means after the cause of a stop has
been removed. This function is also called “reset”.
NOTE: The reset (clearing of the Start/Restart interlock) of
the device must not cause hazardous motion or a hazardous
situation, but only enable the normal start command.
Supplemental Guarding: Additional safeguarding device(s) or
hard guarding, used to prevent a person from reaching over,
under, through or around the primary safeguard or otherwise
accessing the guarded hazard.
Test Piece: An opaque object of sufficient size used to block a
light beam to test the operation of a safety light screen.
Trip Condition: The response of the safety outputs (e.g.,
OSSDs) of a safety light screen when an object equal to or
greater than the diameter of the specified test piece enters the
defined area. In a Trip condition, the OSSDs simultaneously
de-energize. A Trip condition clears (resets) automatically
when the object is removed from the defined area. (See Latch
Condition.)
Trip Initiate: The resetting of a safeguard causing the initiation
of machine motion or operation. Trip Initiate is not allowed
as a means to initiate a machine cycle per NFPA 79 and ISO
60204-1, and is commonly confused with PSDI.
UL (Underwriters Laboratory): A third-party organization
that tests products for compliance with appropriate standards,
electrical codes, and safety codes. Compliance is indicated by
the UL listing mark on the product.