Trane TRACER SUMMIT Hardware And Software Installation page 110

Chapter 7 Network communication
98
Configuring a BACnet-compatible device
A BACnet-compatible device that communicates using an EIA-232 con-
nection with the BCU must meet the following parameters:
Communication at 9,600 baud
•
8 data bits, 1 stop bit, no parity
•
Cable connection to the BACnet port on the BMTX BCU termination
•
board
Specifications for EIA-232 cable connections
Table 27 provides specifications for the EIA-232 cable used to connect the
BMTX BCU to a BACnet-compatible device.
Table 27: EIA-232 cable specifications
Specification Description
Length 50 ft (15.24 m) maximum
For longer distances use a short haul modem.
Shield Shield the cable to comply with FCC regulations and
to protect the BCU from electrical noise.
Figure 34 shows the DB-9 pin assignments for a BACnet device and a
BMTX BCU.
Figure 34. DB-9 connector cable pin connections
BACnet device
Receive data pin assignment
Transmit data pin assignment
Signal ground pin assignment
BMTX BCU
BACnet port: 9-pin male connector
Pin 3 = Transmit data (output)
Pin 2 = Receive data (input)
Pin 5 = Signal ground
Pin 1 = DCD
Jumpered
Pin 7 = RTS
Com = 1
IRQ = 4
BMTX-SVN01C-EN