EverFocus EDR-1610A - Manual (Page 15)

EDR910_1610_ma_en_rev1 00 - 15 -
If star wiring is inevitable, EDA 997A RS-485 signal distributors may be used. The
maximum system cable length can also be expanded by using these distributors,
physically providing a new RS-485 bus with 1200 m cable length each at every
distributor output.
In case the maximum number of 32 bus participants is exceeded, the number of
connected devices can be increased by using RS-485 distributors. Each distributor output
physically provides one RS-485 bus which enables the additional connection of 31 further
devices (the distributor output represents one bus participant itself).
The maximum system expandability depends on the RS-485 address range of the
installed devices.
ATTENTION: The RS-485 signal distributor EDA997A is unidirectional! This means that
the signal only flows from the input towards the outputs. Therefore, e.g. the
interconnection of several keyboards is not possible with this signal distributor!
Star wiring with RS-485 signal distributor
System expansion with RS-485 signal distributor