Fuji Electric FRENIC-AQUA series, User Manual

Page: 656 / 751

8.1 Overview on RS-485 Communication
8-3
Chap. 8
RUNNI
NG TH
ROUGH
RS-4
85
COMMUNI
CA
TION
8.1.2 Terminal specifications for RS-485 communication
[ 1 ] RS-485 communications port 1 (for connecting the keypad)
The port designed for a standard keypad uses an RJ-45 connector having the following pin
assignment:
Pin Signal name Function Remarks
1 and 8 Vcc Power source for the keypad 5 V power lines
2 and 7 GND Reference potential Grounding pins
3 N/A Not available. No connection
6 NC Not used. No connection
4 DX- RS-485 data (-)
5 DX+ RS-485 data (+)
Built-in terminating resistor: 112
Ω
Open/close by SW3*
* For details about SW3, refer to Chapter 2, Section 2.3.2 "Setting up the slide switches."
Pins 1, 2, 7, and 8 on the RJ-45 connector are exclusively assigned to power supply and
grounding for keypads. When connecting other devices to the RJ-45 connector, take care not
to use those pins. Failure to do so may cause a short-circuit hazard. Use pins 4 and 5 only.
[ 2 ] RS-485 communications port 2 (control circuit terminals)
The FRENIC-AQUA has terminals for RS-485 communications on the control circuit terminal block.
The details of each terminal are shown below.
Signal name Function Remarks
SD Shield terminal
DX － RS-485 data (-)
DX ＋ RS-485 data (+)
Built-in terminating resistor: 112
Ω
Open/close by SW2*
* For details about SW2, refer to Chapter 2, Section 2.3.2 "Setting up the slide switches."