Hitachi P1-00250HFEF Basic Manual page 39

Chapter 2
■Serial communication
(Wiring example)
Modbus communication
CM1 SP
(+)
Connect CM1
Into the SG (signal ground) of
external devices,
Terminal
Terminal name
label
SP
SN
RP
(CM1)
■24V power supply input/output
(Wiring example)
Terminal
Terminal name
label
24V output
P24 power source
terminal
Reference
CM1 terminal for
24V output
Terminal for
P+ external 24V
input (24V)
Terminal for
P- external 24V
input (0V)
SN SP SN RP
(-)
For enabling the termination
resistor, short-circuit between
RP and SN.
SP terminal: RS-485 differential(+) signal
SN terminal: RS-485 differential(-) signal
RP terminal: Connect to SP through a termination
MODBUS resistor
terminal CM1 terminal: Connect to the signal ground of
(RS-485) external communication devices.
There are two SP and two SN terminals, which are
connected internally.
The maximum baud rate is 115.2kbps.
Control circuit terminal
External 24V
Power supply
24V terminal
terminal
P24 P+
External DC24V power supply
This terminal supplies DC24V power for contact signals.
This serves as a 0V reference terminal for contact signal.
This is used also as a common terminal for FM output.
Input external DC24V power supply to the inverter.
24V power supply input permit to change parameter
settings and perform optional communication
operations without control power supply.
Control circuit terminal
•
SP and SN with the same name are internally connected, which are
available for a plurality of wiring.
•
For the use of Modbus communication, refer to the "User's guide"
to obtain a more detailed description.
Description
•
Connecting DC24V external power supply into the terminal P+ and
P-, permit to change parameters and perform optional
communication without the main power source. Is also allowable
P-
when connecting into the main power supply.
Description
2-23
Installation and Wiring
Electric characteristics
Termination resistor (120Ω) integrated
Enabled: RP-SN shorted
Disabled: RP-SN opened
Electric characteristics
Max. output 100mA
Allowable input voltage
DC24V±10%
Max. allowable current 1A