Eos –Gate Installation and operation manual
All the information provided with this document are property of Carlo Gavazzi Controls SpA
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10.1.3 RS-485 grounding
Communication through a RS-485 system is made by means of
a balanced pair with a common so a three wire connection is
needed . The Common circuit must be connected directly to
protective ground, preferably at one point only for the entire bus.
Generally this point is to choose on the master device or on its
tap and not to be shared with other devices (inverters,…) which
could add external noise or disturbance.
The protective shield may be used as Common circuit.
10.1.4 RS-485 shielding
A shielded cable is requested to guarantee high degrees of immunity to EMC and lightning events.
The cable shield can be used as Common circuit .
10.1.5 RS-485 topology
Due to signal reflection issues, topology is not free, but only
certain configurations are allowed. The only configuration
which guarantees a sufficient reliability level is the daisy-
chain.