Wintriss wpc 2000, User Manual

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1128500 WPC 2000 User Manual
A-8 Extracts from OSHA and ANSI
8.6.3.7 Muting of the device shall be
accomplished in a manner that conforms to the
requirements of 6.11 and 8.8. E8.6.3.7 Muting is typically accomplished by
interface circuits or auxiliary controls. The
muting element should incorporate a similar
level of control reliability as the presence-
sensing device itself. A simple cam-operated
limit switch wired in parallel with the device’s
output is inadequate, as its failure can remain
undetected.
8.6.3.8 The device shall have an identifiable
minimum object sensitivity so that an obstruction
of an equal or greater size will be detected
anywhere within the sensing field regardless of
the plane of intrusion. E8.6.3.8 The device should have a minimum
object sensitivity stated by the device supplier.
For example, an electro-optical device may
detect a 32 mm (1¼ inch) diameter opaque
object anywhere in its sensing field but allow 25
mm (1 inch) obstructions to pass undetected at
certain points in the field.
8.6.3.9 The device shall have a maximum
response time, which shall not be affected by
object sensitivity adjustments or environmental
changes. E8.6.3.9 The device supplier should state the
maximum total response time, including output
devices, of the presence-sensing device.
8.6.3.10 Devices which require adjustments to
accommodate variations in operating conditions,
or which incorporate fixed blanking or floating
blanking features, shall be designed so that the
adjustments or features are capable of
supervisory control by the user. E8.6.3.10 Typically, these adjustments or
controls are key-operated or located under
lockable covers.
8.6.3.11 The device shall be provided with a
means that visibly indicates when it is
functioning properly. E8.6.3.11 Red and green indicators or other
means that can be easily seen by the operator
and others should be provided to indicate that
the device is functioning.
Indication that the sensing field is being blanked
shall be provided. For fixed blanking, the
blanked area shall be identified. Supplemental
safeguarding shall be provided to prevent
access to the hazard through the fixed blanked
area. The blanking function of a presence-sensing
safeguarding device desensitizes a portion of
the sensing field by disabling one or more
channels such that a specific interruption is
ignored. Presence-sensing devices can be
provided with either fixed or floating blanking.
For fixed blanking, the desensitized area does
not move or change once configured. Floating
blanking allows the blanked area to move within
the sensing field.
Means to identify the desensitized area may
include but are not limited to:
a) Indicators within the device;
b) Signage or marking of the fixed blanked
area;
c) The physical location of the object in the
blanked area if movement or removal of
the object can be detected and it results in
a stop command.
Extracts from ANSI B11.1-2009 8.6.3
Standards Requirements Explanatory Information