Fox Thermal FT2A, Руководство пользователя

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Modbus/BACnet
18
DISCL
AIMER
BA
CNE
T WIRING
TS7 TS1
TS2
TS8
1 2 3
1
1
2
3
4
5
1 2 3
1
2
3
4
5
6
7
8
9
10
11
W1
Tx/Rx (+)
Communication Common
Tx/Rx (-)
Pin 1 of termination resistor header
W1
NC (Termination resistor Not Connected)
TERM (Termination resistor installed)
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RS485 Wiring: BACnet MS/TP
Wiring connections are made to terminal block TS2 for BACnet MS/TP communication.
The Tx/Rx+ signal connects to pin 7, Tx/Rx- connects to pin 8 and communication common to
pin 9 as shown in Figure 8.1.
Termination Resistor
Connect a termination resistor across the receive/transmit signals of the last device on the
BACnet MS/TP communication line. To connect the 121 ohm termination resistor on the FT2A,
set jumper W1 to the TERM position.
Disconnect the termination resistor on all other external BACnet MS/TP devices. The
termination resistor of the FT2A is disconnected by setting jumper W1 to the NC (Not
Connected) position.
Fig. 8.1: BACnet MS/TP Wiring
i
Note: W1 jumper will either be in the NC or TERM position. It should be in the TERM
position on the last meter in the BACnet MS/TP daisy chain.
RS485 Wiring: BACnet MS/TP
Modbus/BACnet