Yaskawa E7L Drive Bypass - Manual (Page 256)

Communications D - 4
Communication Connection Terminal
Modbus communication uses the following terminals: TB4-1 (S+), TB4-2 (S-), TB4-3 (R+), and TB4-4 (R-). The terminating
resistance must be turned ON only if the Drive is at the very end of the Serial Communication chain. Set the terminating
resistance by turning ON pin 1 of switch S1.
Fig. D.2 Communication Connection Terminals and Terminating Resistance
Fig. D.3 RS-485 Communication Connection
Procedure for Setting Up Communication
Use the following procedure to perform communication with the DDC.
1. Turn OFF the input to the Drive power and connect the communication cable between the PLC and the Drive.
2. Turn ON the input power to the Drive.
3. Set the required communication parameters (H5-01 to H5-09) using the Digital Operator.
4. Turn OFF the input to the Drive power, and check that the Digital Operator display has completely disappeared.
5. Turn ON the input power to the Drive once again.
6. Perform communication with the DDC.
IMPORTANT
1. Separate the communication cables from the main circuit cables and control circuit wiring.
2. Use shielded cables for the communication cable, and use proper shield clamps.
3. When using RS-485 communication, connect S+ to R+, and S- to R-, on the control circuit terminal
board. See Fig. D-3 below.
4. Shield at one end only.
Terminating resistance (1/2W, 110 Ohms)
RS-422A
or RS-485
Switch
S1
O
F
F
1
Terminating
resistance
DIP Switch S1-1 located on
E7L terminal board.
2
1
TB4-4 TB4-1 TB4-2 TB4-3