Honeywell HC900 사용자 설명서

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Components and Architecture - Ethernet Devices/Considerations 
16 
  HC900 Hybrid Controller Installation and User Guide 
Revision 5 
  
9/03 
Note:  PDE communications, discussed previously, do not use the PC host connection sockets.  PDE 
communications are separate from (and are transmitted concurrent with) PC host-to-controller 
communications.  
The PC host can include software that closely relates to and supports controller functioning and can also 
include other software that is related remotely or not at all.  Closely related software can include: 
Either  
Hybrid Control Designer - for generating and managing configuration files,  
Or  
HMI (Supervisory/Data Acquisition Software) or Operator Panel with Modbus/TCP driver 
Or  
Both configuration and HMI software (and or panel) 
 
All communications between a controller and a PC host use Open Modbus/TCP protocol, whose 
widespread use is making it an industry standard.  Modbus/TCP is basically an adaptation of the Modbus 
messaging structure that uses TCP/IP for a message carrier.  Modbus messaging is available in two 
versions: ASCII, in which each eight-bit byte is sent as 2 ASCII characters, and RTU, in which each byte 
is sent as two four-bit hexadecimal characters.  Each Modbus message frame is embedded into a TCP/IP 
datagram as indicated in Figure 14. 
 
Figure 14 - Modbus/TCP Framing 
The HC900 Controller uses either Modbus/TCP or  Modbus RTU.  The Modbus mapping structure for 
the HC900 Controller is based on the mapping structure employed in Honeywell’s UMC800 Controller, 
and the function codes and methods for parameter access are also virtually identical.   
From an implementation and installation aspect, the use of the Modbus protocol for HC900 Controller 
configuration differs from the use for Controller-to-HMI communications.  The Hybrid Control Designer 
configuration package, which is supplied by Honeywell, is ready for use as soon as it is installed.  This 
package uses a subset of Modbus function codes that provide for very efficient and secure configuration 
transactions.  Communications details are transparent to the user; all communication drivers are included 
with the package, and no mapping or other detailed setup is required.  
HMI Supervisory/SCADA software is available from various suppliers, and functionality and setup 
requirements vary with suppliers and with specific products.  In all cases, the software selected must be 
compatible with Open Modbus/TCP protocol. 
The user can use the standard Modbus command set to generate a custom set of drivers for his specific 
application, or may purchase additional software (for example, OPC with Modbus /TCP protocol) to 
reduce or virtually eliminate development tasks.