HI 6600 Series Modular Sensor System User Guide
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Profibus-DP
The Profibus®-DP (Decentralized Peripherals) communication profile is designed for efficient field-level
data exchange. Central automation devices, such as PLC/PC or process control systems, communicate
through a fast serial (RS-485) connection with distributed field devices, e.g. PLCs.
To begin communicating weighing parameters between an HI 6000 Series controller and a PLC, PC or DCS
system controller, you need only to load the *.GSD file and set the node address.
Wiring: For Profibus, connect the two wires to pins 3 and 4.
GND SHIELD TX+ TX-
Signal
Ground
Do NOT
Connect
TXD+ /RXD+
Non-inverting
TXD-/RxD-
Inverting
Profibus Configuration
Profibus-DP operates using a cyclic transfer of data between master(s) and slave(s) on an RS-485 network.
An assigned master periodically requests (polls) each node (slave) on the network. The HI 6600 is a slave
device. All data communication exchanges between a master and the HI 6600 originate from the master
device. Each HI 6600 is assigned to one master and only that master may write output data to that HI 6600.
Other masters may read information from any slave, but can only write output data to their own assigned
slaves.
Because Profibus uses a cyclic (periodic) polling mechanism between masters and slaves, it is also
deterministic. Therefore, behavior of a Profibus system can be reliably predicted over time. Profibus is
designed to guarantee a deterministic response.
The length (and timing) of the I/O data to be transferred from a single slave to a master is predefined in the
slave's device data base or GSD file. The GSD files of each device connected via the network (slaves and
class 1 masters only) are compiled into a master parameter record which contains parameterization and
configuration data, an address allocation list, and the bus parameters for all connected stations. A master uses
this information to set up communication with each slave during startup. Slaves can only acknowledge the
messages they receive or transfer messages to a master when the latter requests a slave to do so. Slaves are
also designated as passive nodes.
Refer to the section, “I/O Tables For Communications to PLCs,” in Appendix A for an understanding of
the data and format for the Profibus communications.
For a full list of command parameters, please see the "Default Parameter IDs and Values" in Appendix B.
NOTE
Profibus-DP provides a very flexible network solution. In addition to the basic
guideline provided in this manual, your installation could require procedures that
are
beyond the scope of this manual. For more information and to locate lists of
links to
other sources of Profibus-DP information, check the Profibus website at
http://www.profibus.com.
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