Rs-485; Optical Eye; M-Bus Output; Current And Voltage - Kamstrup M-Bus Master MultiPort 250D Installation And User Manual

3.5

RS-485

M-Bus Master MultiPort 250D's RS-485 connection can be used for M-Bus communication on an equal basis with the
other serial connections.
The following communication speeds can be used for M-Bus communication:
• 300 baud 8E1
• 2400 baud 8E1
• 9600 baud 8E1
Maximum recommended cable length is 1,200 m.
The master's integrated port controller makes sure that communication is only possible on one serial port at a time.

3.6 Optical eye

M-Bus Master MultiPort 250D's optical eye can be used for M-Bus communication on an equal basis with the other
serial connections.
The following communication speeds can be used for M-Bus communication:
• 300 baud 8E1
• 2400 baud 8E1
• 9600 baud 8E1
The master's integrated port controller makes sure that communication is only possible on one serial port at a time.
3.7

M-Bus Output

All meters in an M-Bus network are connected to M-Bus output terminals 24 and 25. The master includes four sets of
connections coupled in parallel.
3.7.1

Current and voltage

Bus mark/space
Detection level, communication
Detection level, collision
Max normal operating current
Warning level, operating current
Overload level, operating current
Kamstrup A/S • 5512853_C1_GB_01.2017
41 V DC/28 V DC
7 mA
25 mA
375 mA
377 mA - Overload LED flashes
500 mA - Overload LED is constantly illuminated
M-Bus Master MultiPort 250D
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