Fuji Electric FRENIC-Ace series - 2 ] Requirements for the Cable (COM Port 1: for RJ-45 Connector); 3 ] Requirements for the Cable (COM Port 2: for RS-485 Connector); 4 ] Branch Adapter for Multi-Drop; Noise Suppression

9.1 Overview of RS-485 Communication
9-9
COMMUNICATION FUNCTIONS
Chap 9
[ 2 ] Requirements for the cable (COM port 1: for RJ-45 connector)
Use a standard 10BASE-T/100BASE-TX LAN cable (US ANSI/TIA/EIA-568A category 5 compliant, straight cable).
The power supply for keypad is available in the RJ-45 connector for RS-485 communication (COM port
1) (pins 1, 2,
7 and 8). When connecting other devices to the RJ-
45 connector, take care not to use
those pins. Use pins
4 and 5 only.
[ 3 ] Requirements for the cable (COM port 2: for RS-485 connector)
To ensure the reliability of connection, use twisted pair shield cables for long distance transmission AWG 16 to 26.
Recommended LAN cable manufacturer:
FURUKAWA Electric Co., LTD AWM2789 cable for long distance connection
Type (Product code): DC23225-2PB
[ 4 ] Branch adapter for multi-drop
The RJ-45 connector is used as the communication connector. To use a standard LAN cable for multi-drop
connection, use the branch adapter for the RJ-45 connector.
Recommended branch adapter
SK Koki (Japan): MS8-BA-JJJ
9.1.5 RS-485 noise suppression
Depending on the operating environment, the malfunction may occur due to the noise generated by the inverter.
Possible measures to prevent such malfunction are: separating the wiring, use of shielded cable, isolating the
power supply, and adding an inductance component. The description shown below is an example of adding an
inductance.

Refer to the RS-485 Communication User’s Manual, Chapter 2, Section 2.2.4 “Precautions for long wiring
(between inverter and motor)” for details.
Adding inductance components
Keep the impedance of the signal circuit high against the high-frequency noises by inserting an inductance
component, such as by inserting a choke coil in series or passing the signal line through a ferrite core.
Figure 9.1-5 Adding an Inductance Component