2.3.2 Control Reliability: Redundancy and Self-Checking
Redundancy requires that the SX5 Safety Laser Scanner circuit components be backed up to the extent that, if the failure of
a single component will prevent effective machine stopping action when needed, that component must have a redundant
counterpart which will perform the same function. The SX5 Safety Laser Scanner is designed with redundant
microprocessors.
Maintain redundancy whenever the SX5 Safety Laser Scanner is in operation. Because a redundant system is no longer
redundant after a component has failed, the SX5 Safety Laser Scanner is designed to monitor itself continuously. A
component failure detected by or within the self-checking system sends a stop signal to the guarded machine and puts the
SX5 Safety Laser Scanner into a Lockout condition.
A recovery from this type of Lockout condition requires:
• Replacing the failed device (to restore redundancy, only performed by Banner Engineering Corp.)
• Performing the appropriate reset procedure
Use the Diagnostic Display to diagnose causes of a lockout condition. See
on page 82.
2.3.3 Application Checklist
The SX5 Safety Laser Scanner can provide a protective function only when its settings and connections (software
configuration, Safety and Warning Zone dimensions, electrical interfacing, mounting, environmental conditions,
supplemental safeguarding, etc.) are coordinated with its application. The checklist items below and the following
application examples are intended to give additional guidance in applying the SX5 Safety Laser Scanner.
The following items are provided to assist in creating a checklist or to be included in a risk assessment for the application of
the SX5. Additional items may be required, depending on the application.
• Review this instruction manual
• Identify the appropriate application (required resolution, field orientation, etc):
◦
Expert for horizontal applications
◦
Vertical for vertical applications
• Determine the area to be safeguarded and the SX5's installation location and means.
• Determine whether the SX5 requires protection from mechanical damage.
• Ensure that the environmental conditions do not exceed the SX5 specifications.
• Determine the size and coverage of the Safety Zone and Warning Zone (if used) depending on:
◦
Physical location of the SX5 installation,
◦
The minimum safety distance or the stopping distance of the mobile vehicle
◦
The height (H) of the Protective Field (horizontal applications)
◦
Other factors that may require an increased minimum safety distance (e.g. "shadowing", adjacent SX5,
retro-reflective surfaces, brake performance degradation)
•
Important: It is recommended to visibly mark the Protective/Warning Field boundaries, if possible.
• Assess the possibility of avoiding detection by the SX5 by climbing/stepping over, crawling under, moving around
the protection field(s), either at the perimeter of the fields or in unprotected areas caused by the shadow effect.
• Determine whether additional/supplement safeguarding is required.
• Determine the proper startup, start/restart (manual/automatic reset), and other safety-relevant parameters. If the
manual restart is used, determine the position for the reset button.
• Determine whether Zone Set switchover is required and identify the conditions for its use.
• Determine whether the Reference Point function is required (at least three (3) reference points must be defined on
fixed surface(s)).
• Determine the method and means of electrical interfacing dependent on the level of risk determined by the risk
assessment (e.g., OSHA/ANSI control reliability or ISO 13849-1 category 3 PLd).
2.3.4 Sample Applications
The SX5 Safety Laser Scanner is used to detect people who are approaching a hazardous area, before reaching it, to
prevent hazardous circumstance (i.e. mechanical movement) that may cause an accident.
The protective detection is done by defining a safety area (the red zone in the figures), whose shape and dimensions must
be designed according to the risk assessment of the machine. The user must consider the position of the hazardous points,
the shape of the machine and of the environment that surrounds it, and the time needed to stop the dangerous movement.
To better ensure people's safety, it is possible to define a warning area (the green zone in the figures): if a person or an
object is approaching too close to the safety area, the safety laser scanner can trigger warning devices. This warning area
cannot be used for safety purposes.
SX5 Safety Laser Scanner
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