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7. INSTALLATION
7.1. General RS-485 bus installation
EKB 500 uses a RS-485 simplex wiring; the signal is transferred via a single twisted pair line.
CAT5 network cable is recommended, UTP version (unshielded) is sufficient for normal application. A
shielded cable should be used if the installed cables are expected to be highly susceptible to interferences.
The number of devices installed in one bus is limited to 32 (expandable through signal distributors), while
max. 8 EKB 500 keyboards may be installed in one system.
Basically, the bus should be created by serial wiring.
Maximum RS-485 bus cable length is 1200 m.
Maximum cable length from box to device is 2m using connector boxes (e.g. EDA-998).
Star wiring is permitted only with signal distributors.
Für Sternverdrahtung können RS-485 Signalverteiler EDA-997A verwendet werden. Mit diesen Verteilern
kann auch die maximal verfügbare Kabellänge des Systems erweitert werden, an jedem Ausgang des
Verteilers steht ein physikalisch neuer RS-485 Bus zur Verfügung (mit jeweils 1200 m Kabellänge).
WRONG !