Roberts Gorden CORAYVAC Installation Manual page 96

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ROBERTS GORDON CORAYVAC
• Terminal connection for ELA-485 2 wire
• Terminal connection for ELA-485 4 wire
Wiring specifications
• A dedicated 24 AWG to 18 AWG twisted pair wire
(EIA-485)
• 2000' (610 m) for 76.8 kbps
• 3000' (914.4 m) for 9600 bps, 19.2 or 38.4 kbps,
before needing a Repeater
• Devices should be daisy chained.
• If the controller is at either end of a network seg-
ment, connect a Terminating Resistor (P/N
10061018) to the I/O Pro 812u control board.
Note: Use the same polarity throughout the network
segment.
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M H C C
ODULATING EATING ONTROL
I M
ONTROLLER NSTALLATION ANUAL
7. Turn on power to control board.
8. Set the correct network number to the unique
BACnet MS/TP network at the touch screen.
9. Set a unique Device Instance number.
NOTE:
The most common communication problems are the
result of not properly following the configuration
steps outlined. Review steps and use the following
list to check your settings.
Verify accuracy of the following:
Hardware settings for speaking BACnet MS/TP:
• Baud rate DIP switches 4 and 5
• Protocol DIP switches 6, 7, and 8 jumpers set to
half duplex (2-wire) and EIA-485
• Proper connection wiring
• Unique rotary address switches 1 – 99. If control-
lers have duplicate addresses, network communi-
cation can be lost.
• Unique BACnet Device Instance numbers. Default
is 24XX, with the rotary address switches defining
XX. If controllers have duplicate device instance
numbers, network communication can be lost.
NOTE:
• The controller recognizes physical changes (DIP
switches, rotary switches, and jumpers) upon
power up.