Vacon 20 User Manual

Modbus technical data vacon • 7
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3
3. MODBUS TECHNICAL DATA
3.1 Modbus RTU protocol
Modbus RTU is the only supported transmission mode. Modbus ASCII mode is not supported.
Table 2.
3.2 Connections and wiring
The maximum length of an RS-485 cable depends on the bitrate used, the cable (gauge, capacitance
or characteristic impedance) and the number of devices in the bus. The Modbus RTU specification
states that for a maximum 9600 bits/second bitrate and AWG26 or wider gauge, the maximum
length is 1000 meters. The actual cable length used in an installation can be lower than this number
depending on the aforementioned parameters.
Connections and
communications
Interface RS-485
Data transfer method RS-485 MS/TP, half-duplex
Transfer cable STP (Shielded Twisted Pair)
Connector
2.5 mm
2
Electrical isolation Functional
Modbus RTU
As described in “Modicon Modbus Proto-
col Reference Guide”
Bitrate
300, 600, 1200, 2400, 4800, 9600, 19200,
38400, and 57600 bits/s
Addresses 1 to 247

Vacon 20 Specifications

General

Communication Options	Modbus, CANopen, PROFIBUS, Ethernet
Protection Class	IP20
Power Range	0.25 to 18.5 kW
Control Method	Scalar control, Vector control
Ambient Temperature	-10°C to +50°C