Honeywell HC900 用户手册

Pre-Installation Planning - Equipment Placement Considerations 

Revision 5 

  HC900 Hybrid Controller Installation and User Guide 

41 

9/03  

Factors that determine where equipment should be located within the site include at least the following:  

• 

Environmental conditions (see above). 

• 

Wiring/cabling characteristics.  The HC900 Controller includes (optional) I/O expansion racks (C50 
CPU only), which provide options regarding methods of connecting field devices into the system.  That 
is, the length of I/O wiring can be reduced significantly by locating I/O expansion racks remote from the 
Controller rack, but close to process equipment.  Following are samples of valid system architecture.  

: Cable lengths specified in this manual are absolute.  When planning for routing of cables and wires, 

be certain to include vertical and horizontal routing within cabinets, raceways, and conduits.  For 
planning hints, refer also to Appendix A of this manual. 

Controller Rack, with Local I/O 
(only).  In this case, all wiring is from 
field devices to I/O modules in the 
local rack.  

Maximum length of RS-232 cabling 
(Controller to PC) is 50 feet (15.2 
meters). 

Maximum length of RS-485 cabling 
(Controller to Operator Interface) is 
2000 feet (609.6 meters).   

 

 

Controller rack, with one I/O 
expansion rack.(C50 CPU only) 

Maximum length of Ethernet cabling 
(Controller to I/O expansion rack) is 
328 feet (100 meters). 

 

 

 

 

Controller rack connected via 
Ethernet Hub to up to four I/O 
expansion racks. (C50 CPU only) 

Length of Ethernet cable: 

• 

(Local Rack to Ethernet Hub):  
≤ 328 feet (100 meters) 

• 

Hub to any I/O expansion rack - 
 ≤ 328 feet (100 meters)