Hitachi L2002 - Manual (Page 238)

Introduction
Appendix B
B–2
Introduction
L200 2 Series inverters have built-in RS-485 serial communications, featuring the
ModBus RTU protocol. The inverters can connect directly to existing factory networks
or work with new networked applications, without any extra interface equipment. The
specifications for L200
2
serial communications are in the following table.
The network diagram below shows a series of inverters communicating with a host
computer. each inverter must have a unique address, from 1 to 32, on the network. In a
typical application, a host computer or controller is the master and each of the inverter(s)
or other devices is a slave.
Item Specifications User-selectable
Transmission speed 4800 / 9600 / 19200 bps
✔
Communication mode Asynchronous
✘
Character code Binary
✘
LSB placement Transmits LSB first
✘
Electrical interface RS-485 differential transceiver
✘
Data bits 8-bit (ModBus RTU mode) (ASCII mode not
available)
Parity None / even / odd
✔
Stop bits 1 or 2 bits
✔
Startup convention One-way start from host device
✘
Wait time for response 0 to 1000 msec.
✔
Connections Station address numbers from 1 to 32
✔
Connector RJ45 modular jack —
Error check Overrun, Fleming block check code,
CRC-16, or horizontal parity —
L200 2
1 2
RUN STOP RESET
FUNC. STR
HITACHI POWER
ALARM
RUN
A
Hz
PRG
5 0.0
L200 2
1 2
RUN STOP RESET
FUNC. STR
HITACHI POWER
ALARM
RUN
A
Hz
PRG
5 0.0
L200 2
1 2
RUN STOP RESET
FUNC. STR
HITACHI POWER
ALARM
RUN
A
Hz
PRG
5 0.0
1
ModBus Network
2 32
Host computer