janitza UMG 806, Руководство пользователя и технические данные

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UMG 806 www.janitza.com
7.8 RS-485 interface
The serial RS-485 interface of this device is de-
signed as a 2-pole screw contact and communi-
cates using the Modbus RTU protocol.
For the connection capacity of the terminals, see
chapter „16. Technical data“ on page 86.
Examples
RS-485 bus
A
B
A
B
Connection of
additional devices
INFORMATION
· The device does not contain an integrated termi-
nation resistor. A termination resistor must be set
for termination for a UMG 806 at the beginning or
end of a bus segment, (see section "Termination
resistors / Termination").
· CAT cables are not suitable for bus wiring!
Recommendation: Use Unitronic Li2YCY(TP)
2x2x0.22 (Lapp cable) for bus wiring.
· A segment of an RS-485 bus structure can contain
up to 32 nodes/devices. If there are more than 32
nodes/devices, use repeaters to connect seg-
ments.
Illustration example:
RS-485 interface of the UMG 806 (in the middle of a bus
topology)
Connection of
additional
devices
RS-485 bus
A
B
Fig. Example:
RS-485 interface of the UMG 806 (at the begin-
ning of a bus topology)
120 Ω
WARNING
Risk of injury or damage to the device due to
electrical voltage and improper connection!
High measuring currents can cause temperatures
of up to 80 °C (176 °F) at the connections.
Use wiring designed for an operating tempera-
ture of up to 80 °C (176 °F)!