Hitachi SJ700-055HFF2, Instruction Manual

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Chapter 4 Explanation of Functions
4.4 Communication Functions
The inverter can engage in RS485 communications with an
external control system that is connected to the TM2 terminal
block (on the control circuit terminal block board) of the inverter.
A001: Frequency source setting
A002: Run command source setting
C071: Communication speed selection
C072: Node allocation
C073: Communication data length selection
C074: Communication parity selection
C075: Communication stop bit selection
C078: Communication wait time
C079: Communication mode selection
Related code
The SJ700 series inverter shares the ASCII communication
protocol with the SJ300 and L300P series inverters.
(1) Communication specifications
Item ASCII mode Modbus-RTU mode Remarks
Transmission speed 2,400, 4,800, 9,600, or 19,200 bps Selection with the digital operator
Communication method Half-duplex communication
Synchronization method Start-stop transmission
Asynchronous
transmission
Transmission code ASCII code Binary code
Transmission method Transmission beginning with the lowest-order bit
Applicable interface RS485
Data bit length 7 or 8 bits 8 bits Selection with the digital operator
Parity No parity, even parity, or odd parity Selection with the digital operator
Stop bit length 1 or 2 bits Selection with the digital operator
Initiation method
Initiation only by a command from the external
control system
Waiting time 10 to 1,000 ms 0 to 1,000 ms Setting with the digital operator
Connection format 1-to-N connection (N: Maximum of 32 [inverters])
Station number to be selected
with the digital operator
Error check
Overrun, framing, BCC,
vertical parity, and
longitudinal parity errors
Overrun, framing, CRC-
16, and longitudinal
parity errors
<Specifications and connections of RS485 ports>
For the RS485 communication function, use the TM2 terminal block on the control circuit terminal block
board.
Control circuit block
Abbreviated
name of
terminal Description
SP
Positive signal terminal
for transmission
SN
Negative signal terminal
for transmission
RP
Terminal to enable the
terminating resistor
SN Terminal to enable the
terminating resistor
Control circuit
block board
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