Bender A-ISOMETER IRDH375 - RS485 Interface

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Interface
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RS485 interface
The electrically isolated RS485 interface serves as a physical transmission
medium for the BMS protocol. If several IRDH375B are interconnected in a
network via the RS485 bus, the RS485 bus must be terminated at both ends
with a 120 Ohm resistor (switch S1 = ON). An RS485 network that is not
terminated is likely to get instable and may result in malfunctions. Only the
fi rst and the last device may be terminated. Devices in between may not
be terminated. If there are stub feeders in the network, these must not be
terminated. The length of the stub feeders is restricted to 1 m.