8
TECHNICAL DATA
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WATERFLUX 3070
www.krohne.com
06/2016 - 4004999701 - MA WATERFLUX 3070 - R01 en
8.5 Modbus protocol (option)
The Modbus option on the WATERFLUX 3070 is available in two versions:
•
not isolated (battery powered) - for standard internal battery version
•
galvanically isolated (mains powered) - for KROHNE FlexPower version
The WATERFLUX 3070 flow converter and FlexPower with Modbus has a RS485 interface to
communicate with an external device (PC or other suitable computer system) using the Modbus
protocol. This option allows data exchange between PC or computer and single or multiple
devices. The bus configuration consists of one external device as a master and one or more
converters as slaves.
For bus operation, the device address, parity, baud rate , stop bits, data format and transmission
delay must be set in the signal converter. All devices connected to the bus, must have the same
baud rate and settings, but different (unique) addresses.
General technical data
CAUTION!
Please note that changing the baud rate will greatly affect the units battery life time. The baud
rate equal to and below 9600 bps are considered energy efficient while baud rates greater than
9600 bps are not.
Baud rate
1200, 2400, 3600, 4800, 9600 (default), 19200, 38400, 57600 or 115200
Protocol
Modbus RTU (documentation available on the Modbus Organisation
website)
Data encoding
All Modbus data fields are encoded according to the IEC 61131-3
standard
Maximum participants on bus
32 per line, master included (may be extended by repeaters)
Coding
NRZ bit coding
Address range
Modbus: 1...247
Transmission procedure
Half duplex, asynchronous
Bus access
Master / slave
Device role
Slave
Cable
Shielded twisted pair for RS 485 applications
Distances
Isolated: Maximum 1.2 km / 3937 ft without repeater (dependent on
baud rate and cable specifications) multi-drop
Non isolated: Maximum 100 m, without termination (point to point)
INFORMATION!
For more details refer to the Modbus supplementary manual.