15Kmstrup A/S • 5512853_C1_GB_01.2017
M-Bus Mster MultiPort 250D
3.5 RS-485
M-Bus Mster MultiPort 250D’s RS-485 connection cn be used for M-Bus communiction on n equl bsis with the
other seril connections.
The following communiction speeds cn be used for M-Bus communiction:
• 300 bud 8E1
• 2400 bud 8E1
• 9600 bud 8E1
Mximum recommended cble length is 1,200 m.
The mster’s integrted port controller mkes sure tht communiction is only possible on one seril port t time.
3.6 Opticl eye
M-Bus Mster MultiPort 250D’s opticl eye cn be used for M-Bus communiction on n equl bsis with the other
seril connections.
The following communiction speeds cn be used for M-Bus communiction:
• 300 bud 8E1
• 2400 bud 8E1
• 9600 bud 8E1
The mster’s integrted port controller mkes sure tht communiction is only possible on one seril port t time.
3.7 M-Bus Output
All meters in n M-Bus network re connected to M-Bus output terminls 24 nd 25. The mster includes four sets of
connections coupled in prllel.
3.7.1 Current nd voltge
Bus mrk/spce 41 V DC/28 V DC
Detection level, communiction 7 mA
Detection level, collision 25 mA
Mx norml operting current 375 mA
Wrning level, operting current 377 mA - Overlod LED flshes
Overlod level, operting current 500 mA - Overlod LED is constntly illuminted