6 -96Communications Connection TerminalMEMOBUS communications use the following terminals: S+, S-, R+, and R-. Set the terminating resistanceby turning ON pin 1 of switch S1 for the last Inverter only, as seen from the PLC.Fig 6.58 Communications Connection TerminalProcedure for Communicating with the PLCUse the following procedure to perform communications with the PLC.1. Turn OFF the power supply turned and connect the communication cable between the PLC and theInverter.2. Turn ON the power supply.3. Set the required communications constants (H5-01 to H5-07) using the Digital Operator.4. Turn OFF the power supply, and check that the Digital Operator display has completely disappeared.5. Turn ON the power supply once again.6. Perform communications with the PLC.IMPORTANT1. Separate the communication cables from the main circuit cables and other wiring and power cables.2. Use shielded cables for the communication cables, connect the shield cover to the Inverter earth terminal,and arrange the terminals so that the other end is not connected to prevent operating errors due to noise.3. When using RS-485 communications, connect S+ to R+, and S- to R-, on the Inverter exterior.INFOSet the timer on the master to monitor response time from the slave. Set the master so that if the slave doesnot respond to the master within the set time, the same command message will be sent from the masteragain.RS-422Aor RS-485 R+R-Switch1Terminating resistance (1/2 W, 110 Ohms)S+S-+- S1OFF12TerminatingresistanceOFF ONR+ R S+ S
