Perfecta Pro2 Installation And Operating Manual page 8

3.4.6 MODBUS
Data protocol
Modbus connector
Modbus connection
type
Modbus wire
configuration
Communication
transceiver
Maximum cable
length
Slave address
Line termination
Supported
transmission speeds
Start bit
Data bits
Stop bits
Parity bit
Modbus visual
diagnostics
Maximum number of
Modbus devices
Maximum Modbus
packet size
Isolation
Modbus specification
Modbus RTU
Screwless terminals
RS-485
Two-wire + common
Integrated, 1/8 of
standard load
1200 m
1-247
Not present
1200, 2400, 4800, 9600,
19200, 38400 baud
1
8
1 or 2
Even/odd/none
LED2
247
256 bytes
Common ground (COM)
with SET1, SET2 and
SET3.
2+1 pins. See communication manual.
Conductors: A, B and COM (Common).
See communication manual.
Connect either via passive taps or daisy chain.
See communication manual.
Default is 245, settable over Modbus. See
communication manual.
Line termination is not integrated. For low
speed/short distance, termination can be
omitted. Otherwise, terminate the line externally
on both ends.
Settable over Modbus register [default=19200].
Fixed.
Fixed.
1 stop bit minimum, up to 2 when parity not
enabled [default=1]
[default=Even]
Flashing yellow when data reception detected.
Combined (OR) with Ethernet ACT function.
Limited by possible Modbus addresses to 247.
1/8 nominal load enables 256 devices.
Including address (1) and CRC (2) bytes.
Modbus shares common ground with other
signals.
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