PSP10
5-2-55, Minamitsumori, Nishinari-ku, Osaka 557-0063 JAPAN
Phone: +81(6)6659-8201 Fax: +81(6)6659-8510 E-mail: [email protected]
EM-4890 P. 11 / 17
MODBUS COMMUNICATION
Modbus communication allows execution of Auto-setup and monitoring of the operation status of the actuator in the same
manner as the programming unit (model: PU-2x) and the PC configurator software.
Position set point can be input via Modbus instead of analog signal.
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MODBUS COMMUNICATION SPECIFICATION
This unit supports Modbus-RTU protocol.
ITEM
SETTING RANGE
EX-FACTORY SETTING
Node address
1 to 247
1
Baud rate
38400, 19200, 9600, 4800 bps
38400 bps
Parity
None, Odd, Even
None
Stop bit
1, 2
1
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MODBUS COMMANDS
FUNCTION
COMMAND
DESCRIPTION
03
Read Holding Registers
Reads the value(s) of a single or multiple holding registers.
04
Read Input Registers
Reads the value(s) of a single or multiple input registers.
06
Preset Single Register
Presets a value in a single holding register.
16
Preset Multiple Registers
Presets values in respective multiple holding registers.
It is recommended to set timeout for response to 0.5 sec. or longer.
‘0’ is returned when an address to which no register is assigned is read.
An exception response is returned when attempting to write to an address which is not writable.
Even if the address is writable, make sure to set [Modbus Operation mode (address 111)] in advance to enable writing.
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ADDRESS MAP
Refer to “PARAMETER ITEMS COMMON TO MODBUS, CONFIGURATOR SOFTWARE AND PU-2x” for Modbus address
map.
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DATA VALUE
When [Value Range] of the data is specified as numbers with one digit after the decimal point, the data is multiplied by 10
and handled as an integer. That is, ‘25.8’ is handled as ‘258’, for example.
When the data is specified as numbers with two digit after the decimal point, the data is multiplied by 100 and handled as
an integer.
When the Data type is ‘I16’, data is an integer between -32768 to 32767, and when the Data type is ‘I32’, data is a long 32-bit
integer between -2147483648 to 214783647.
Long data is in little endian format.
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POSITION SETPOINT INPUT VIA MODBUS
The position setpoint can be input via Modbus communication by the following procedure.
1) Set [Input mode (Modbus=address 124, PU-2x= ITEM 63)] as ‘Modbus input’.
2) Write a position setpoint value (e.g. ‘700’ for 70.0 %) to Address 101.
3) Write ‘1’ to Address 111 to enable Modbus input, thereby moving the output stem toward the setpoint.
Note)
• When a motor deadlock error occurs, ‘1’ or ‘2’ is set in Address 46.
Write ‘1’ to Address 51 or turn SW-8 ON to clear the error.
• When [Modbus disconnection detection time (Modbus=address 127, PU-2x= ITEM 36)] is set, a Modbus disconnection error
is detected when a Modbus command is not issued for the set time period, thereby causing the output stem to stop, extend
(move downward), or retract (move upward) according to the settings of DIP switches 1-1 and 1-2 of the unit.
• Refer also to “COMBINATION OF OPERATION MODE AND SPECIFICATIONS”.
