KROHNE MFC 400 Modbus - Manual (Page 5)

TECHNICAL DATA
2
5
MFC 400
www.krohne.com 05/2013 - 4002525102 - AD Modbus MFC 400 R02 en
2.1 General technical data
2.2 Technical data of the Modbus interface (acc. to EIA/TIA standards)
Interface RS485, galvanically isolated
Baud rate 1200, 2400, 3600, 4800, 9600, 19200, 38400, 57600 or
115200 bps
Protocol Modbus RTU (available as a separate document on request)
Maximum participants on bus 32 per line, master included (may be extended by repeaters)
Coding NRZ bit coding
Address range 1...247
Transmission procedure Half duplex, asynchronous
Bus access Master / slave
Cable Screened twisted pair
Distances Maximum 1.2 km / 3937 ft without repeater (dependant on
baud rate and cable specifications)
Kind of signal transmission Differential, 2-wire topology
Maximum number of
transmitter/receivers
32
Voltage range on converter input -7...+12 V
Maximum voltage on converter output 5 V
Minimum voltage on driver output, max.
load
U
diff
> 1.5 V
Maximum input current (off state) -20...+20 μA
Receiver input voltage -7...+12 V
Sensitivity of the receiver -200...+200 mV
Receiver input resistance > 12 kΩ
Short circuit current < 250 mA
Termination / polarization resistors
(if activated by factory)
120 Ω / 560 Ω