Star And Multi-Drop Configuration - Vanderbilt SPC42 Series Installation & Configuration Manual

Spur configuration
1 Controller
2-4 Expanders
10.1.3

Star and multi-drop configuration

Max. expanders/keypads
Total cable length
Vanderbilt
All expanders/keypads are fitted with termination jumpers, as default, allowing
termination on all the devices. This is imperative for the spur (chain) configuration,
as the jumper acts as a resisting terminator cancelling echoes on the line.
Within the loop wiring configuration all expanders/keypads are fitted with a jumper,
as default, allowing termination on the device.
NOTICE
Please read the section for wiring examples [➙ 79] and the section Shielding
[➙ 80] before starting the installation.
The star and multi-drop cabling methods enables takeover of existing wirings with
four-core cables in small buildings (typically homes) with low electrical noise
environment. These wiring methods are limited to the specifications below:
SPC42xx/SPC43xx
8
200 m
NOTICE
The performance in star or multi-drop configuration wiring is limited due to non-
optimal conditions of the RS-485 bus specification (reduced signal quality due to
multiple receivers/transmitters in parallel with unbalanced terminating resistors).
Installation & Configuration Manual
Wiring the X-BUS interface
SPC52xx/SPC53xx/SPC63xx
16 (8 per X-BUS port)
200 m
Wiring the system
10
75
A6V10276959
01.05.2016