ACS CANopen Manual
Version 20110928
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AC C E L E N S ( AC S ) C AN o p e n
In simple terms, CANopen works as a client-server
model. Each device checks whether the bus is
free, and if it is free the device can send
messages. If two devices try to access the bus at
the same time, the device with the higher priority
level (lowest ID number) has permission to send its
message.
Devices with the lowest priority level must cancel
their data transfer and wait before re-trying to send
their message. Data communication is carried out
via messages. These messages consist of a
unique COB-ID (refer to glossary) followed by a
maximum of 8 bytes of data. The COB-ID, which
determines the priority of the message, consists of
a function code and a node number. The node
number corresponds to the network address of the
device. It is and has to be unique on a bus in order
to distinguish nodes and prevent any conflict of
interests.
The function code varies according to the type of
message being sent:
•
Management messages (LMT, NMT)
•
Messaging and service (SDOs)
•
Data exchange (PDOs)
•
Predefined messages (Synchronization,
Emergency messages)
1.3 ACS CANopen
The ACS CANopen inclinometer corresponds to
the class 2 inclinometer profile with DS 410
CANopen standards, in which the characteristics of
inclinometers with CANopen interface are defined.
The ACS is available in a completely molded and
rugged plastic housing.
The ACS CANopen series of inclinometers are
available in two variants. First, a single axis
measurement variant with a range of 0-360° (
either clockwise or anti-clockwise) and the other
variant, a dual axis measurement capable ACS
model with a range of ±80°.
In addition to high resolution, accuracy and
protection class of IP69K, it has in-built active
linearization and temperature compensation. This
makes ACS suitable for rugged environments and
versatile applications in industrial, heavy duty and
military applications.
The inclinometer supports the following operating
modes:
•
Polled
mode:
The
position
value
is
transmitted only on request.
•
Cyclic mode:
The position value is sent
cyclically (regular, adjustable intervals) on the bus.
•
SYNC mode:
The position value is sent after
a synchronization message (SYNC) is received.
The position value is sent every n SYNCs (n ≥ 1).
•
State change mode:
The position value is
transmitted
whenever
the
position
of
the
inclinometer, in continuous operation, changes.
The CANopen bus interface on the ACS
inclinometers, permit transmission rates of up to
1MB (30 m/100 ft cable for a maximum
speed of 1MB, 5000 m/ 16,500 ft cable for a
maximum speed of 10 kB).
