Sensor systems 2 AS-Interface

Issue date 2004-11-19 - Catalogue AS-Interface 2004/2005
6 Inductive AS-Interface Sensors
In previous system concepts with conventional wiring,
the detection of sensor defects was difficult and would
often lead to prolonged machine downtimes.
In a modern system concept, integrated chips provide
sensors with "intelligence" and extend their functionality.
The sensors have an independent self-monitoring
and cable monitoring function, and can output data
messages to a higher-level unit, e.g. to a PLC.
Pre-fault indication
In practice, inductive sensors are set so that the distance
between the object and the sensor corresponds
to approximately 50% of the maximum operating
range. The pre-fault indication is activated if the object
is only active in an area between 80% and 100% of the
maximum operating range. It indicates that the sensor
is out of range. The advantage of this is that the message
is made available before the sensor fails.
Oscillator monitoring
During oscillator monitoring, the oscillator coil is monitored
in order that a fault in the coil, such as an open
circuit, can be detected and indicated.
The 4 data bits in the messages also contain information
about the status of the N.C/N.O. contacts of the
sensor, which can be modified if required by transferring
the appropriate parameter:
Parameter
N.C. contact N.O. contact
31 or 62 of these intelligent sensors can be connected
in a single AS-Interface network per master. Various
types of sensors are available from Pepperl+Fuchs.
Types
Embeddable and built in flush cylindrical sensors are
available in diameters M12 to M30. Conventional sensors
in stainless steel head ferrules with 2 mm round
cable or V1 plug connection with multiple LED display
are available as standard.
VariKont ®
AS-Interface - Inductive Sensors
Rectangular sensors are available as surface-mounting
sensors or in VariKont ® , VariKont M ® and VariKont
L ® housings. The VariKont L ® housing is of particular
interest.
The sensor head is convertible and may be rotated in
15° steps. It is fastened using 2 screws, which are also
used to mount the sensor. This sensor has been developed
specifically for conveying applications.
The VariKont ® and VariKont M ® housings correspond
to the mounting slot requirements of EN 60947 for mechanical
roller rocker end switches. They also permit
the rotation of the sensor heads. The VariKont ® housing
permits the head to be rotated in 90° steps, the VariKont
M ® housing in 15° steps. A special base (U9A)
is available for the VariKont ® housing, which enables
direct connection to the AS-Interface flat cable using
the cable-piercing technique.
Subject to reasonable modifications due to technical advances. Copyright Pepperl+Fuchs, Printed in Germany
Pepperl+Fuchs Group Tel.: Germany +49 621 776-0 USA +1 330 4253555 Singapore +65 67799091 Internet http://www.pepperl-fuchs.com
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Masters and
Gateways
Power Supplies,
Extender, Repeaters
Safety at work
I/O Modules
Control cabinet
I/O Modules
Field application
Analogue modules
Other modules
Inductive sensors
Photoelectric
sensors
Rotary encoders
Accessories