Balluff BOS R254K-UUI-LH10-S4, Manual

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2.1 General
IO-Link integrates conventional and intelligent sensors and
actuators in automation systems and is intended as a
communication standard below classic field buses. Field-
bus-independent transfer uses communication systems
that are already available (field buses or Ethernet-based
systems).
IO-Link devices, such as sensors and actuators, are
connected to the controlling system using a point-to-point
connection via a gateway, the IO-Link master. The IO-Link
devices are connected using commercially available
unshielded standard sensor cables.
Communication is based on a standard UART protocol
with a 24-V pulse modulation in half-duplex operation. This
allows classic three-conductor physics.
2.2 Protocol
With IO-Link communication, permanently defined frames
are cyclically exchanged between the IO-Link master and
the IO-Link device. In this protocol, both process and
required data, such as parameters or diagnostic data, is
transferred. The size and the type of the frame type and
the cycle time used result from the combination of master
and device features (see communication properties in
section 3.2 on page 9).
2.3 Cycle Time
The cycle time used (master cycle time) results from the
minimum possible cycle time of the IO-Link device
(min cycle time, see section 3.2 on page 9) and the
minimum possible cycle time of the IO-Link master. When
selecting the IO-Link master, please note that the larger
value determines the cycle time used.
2
IO-Link Basic Knowledge
2.4 Device Status
The
Device Status
indicates the current status of the
device or of the directly connected peripherals. This
functionality is part of the IO-Link specification.
The following states are output by the device:
– Device is operating properly (device is functioning
error-free)
This status indicates that no serious error has occurred
in the device and the device can be operated without
restrictions.
– Maintenance-Required
Although the process data is valid, internal diagnosis
functions show that the device or the operational
environment of the device should be serviced.
– Out-of-Specification
Although the process data is valid, internal diagnosis
functions show that the device is operating outside of
the specified specification. This can affect both the
measurement application itself as well as the
environmental conditions.
– Functional-Check
Process data is temporarily invalid while a deliberate
intervention is performed on the device. For example,
parameterization processes or teach-in.
– Failure
The device or the connected peripherals have a severe
error . The device cannot perform its intended function!
For further information, see section 6.1 on page 77.
The creation of the
Device Status is always based on the
output of diagnosis messages. A Device Status is output
for every diagnosis message (event). Each of these can be
found in the event overview list (see section 3.6 on
page 20) or in the description of the functions.
2.5 Block Parameterization
Block parameterization refers to a special process in which
multiple parameters are parameterized in one process. It is
started with a start command and concluded with an end
command.
Because the check of the data is not performed until the
parameterization is concluded, pieces of data that are
dependent on one another can also be set without
problem.
BOS R254K-UUI-LH10-S4
Photoelectric Sensors