Hitachi SJ700B SERIES, Instruction Manual

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Chapter 4 Explanation of Functions
4 - 114
Connection
As illustrated below, connect the inverters in parallel to the external control system, and connect the
RP and SN terminals with a jumper on the inverter at the end of the network. (Similarly jumper the RP
and SN terminals when only one inverter is connected to the external control system for RS485
communication.) Connecting the RP and SN terminals enables the terminating resistor in the control
circuit terminal block board of the inverter, which suppresses signal reflections.
(2) Required settings
The following table lists the inverter settings required for the RS485 communication:
Item Function code Data or range of data Description
02 Loopback test
03 2,400 bps
04 4,800 bps
05 9,600 bps
Communication speed
selection
C071
06 19,200 bps
Node allocation C072 1. to 32.
Assignment of a station number to the
inverter
(Set this item when your inverter is
connected together with other(s) to a
control system.)
7 7 bits Communication data length
selection
C073
8 8 bits
00 No parity
01 Even parity
Communication parity
selection
C074
02 Odd parity
1 1 bit Communication stop bit
selection
C075
2 2 bits
00 Tripping
01
Tripping after decelerating and stopping
the motor
02 Ignoring the errors
03 Stopping the motor after free-running
Selection of operation after
communication error
C076
04 Decelerating and stopping the motor
Communication trip limit time
setting
C077 0.00 to 99.99 (s)
Limit length of time to determine
communication train disconnection
Communication wait time
C078 0. to 1000. (ms)
Time to wait until the inverter returns a
response
00 ASCII mode Communication mode
selection
C079
01 Modbus-RTU mode
…
SP SN RP SN
External control
system
SP SN RP SN SP SN RP SN