Cable/Wiring Distance Planning - Honeywell HC900 User And Installation Manual

Cable/Wiring Distance Planning

For all installations observe the following guidelines.

Maximum length of RS-232 cabling (Controller to PC) is 50 feet (15.2 meters).

Maximum length of RS-485 cabling is 2000 feet (609.6 meters).

For Ethernet connections, cable length must be less than 100m. For greater than 100m a switch is
required. The use of Ethernet cables in excess of 100 meters and/or devices other than recommended
Switches will cause transmission delays on the I/O link which could have adverse affects on Controller
performance.

You can also use fiber optic cable for connections between the controller and a remote rack. Please refer
to HC900 specification document

With redundant CPUs, when using 2 or more I/O racks an Ethernet switch is required between each CPU
and the I/O racks. Use Honeywell-approved switches only. (see page 215)
Maximum of 2 switches between each CPU's I/O port and all I/O racks.


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.

It is advantageous to minimize length of I/O wiring. However, it is also a good idea to locate racks (and
wiring) away from adverse environmental conditions such as sources of RFI, EMI, and away from areas
with high levels of moisture, dust, and corrosive materials.
54
(51-52-03-31)
HC900 Process & Safety Controller User and Installation Manual
for more details.
Revision 6
21 April 2017