janitza UMG 604 - Rs485

33
UMG 604
RS485
The RS485 interface is designed as a 2-pole
plug.
RS485 Bus
A
B
A
B
BA
Correct
Incorrect
Terminal strip in the control cabinet.
Device with RS485 interface.
(Without terminating resistor)
Device with RS485 interface.
(With terminating resistor at the device)
Terminating resistors
The cable at the start and end of a segment
is terminated with terminating resistors (120
ohm, 1/4 W).
The UMG604 does not contain any terminating
resistors.
RS485 Bus
A
B
B
A
Fig. RS485 interface, 2-pole plug contact with
terminating resistor (Part no. 52.00.008).
120Ω
Fig. RS485 interface, 2-pole plug contact.