Hardy Process Solutions HI 6500 Series, Руководство пользователя

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Network Configuration
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5. Run the Modbus Function code #4 (read multiple registers). This will allow the
user to read the status of the command in data register #1.
If you wish to then read back the value you have written:
6. Enter the command #0 into data register #0.
7. Run the Modbus Function code #16 (write multiple registers), or Function code
#6 (write single register) insuring the correct data location is being set.
8. Run the Modbus Function code #4 (read multiple registers).
Read the value for the span parameter in data registers #4 & 5. This value will be in
floating point format.
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.
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 6500 or HI 6510 is a slave device. All data communication exchanges
between a master and the HI 6500 or 6510 originate from the master device. Each HI 6500
or HI 6510 is assigned to one master and only that master may write output data to that HI
6500 or HI 6510. 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