Dome Configurations; Star Configuration; Daisy Chain Configuration - American Dynamics AD1273 CobraDome Installation And Operation Instructions Manual

SETUP

Dome Configurations

When using the AD1273 with other domes in a security
system, determine the type of configuration that best suits the
particular application.

Star Configuration

A star configuration refers to the direct hardwiring of one
AD1273 unit to one outlet port of a data distribution unit. A
star configuration limits the number of AD1273 units to the
available number of outlet ports on the data distribution unit.
Each AD1273 unit is equipped with a 120-ohm resistor to
provide a low impedance termination to the data lines between
the AD1273 and the data distribution unit (see Figure 5).
* 120-Ohm Termination
*
B
W
AD1273
S
*
B
AD1273 W
S
*
B
AD1273
W
S
S
Figure 5 - Star Configure Connection
W B
S W B S W B
Data Distribution Unit
S
W B
S
W B
Data Source

Daisy Chain Configuration

A daisy chain configuration triples the number of AD1273
units wired to each outlet port of a data distribution unit (see
Figure 6). A maximum of three AD1273 domes may be daisy
chained on a single data line.
When using the AD1273 in a daisy chain configuration, a
jumper connecting a 120-ohm terminating resistor must be
removed from all but the last dome in the chain (see Figure 6).
Eliminate the termination by removing jumper J2 (see Page 9)
on the printed circuit board mounted to the AD1273 chassis.
NOTE: Retain the 120-ohm termination for the last dome in
the chain.
Other
Receivers
AD1273
S
S
Data Source
Figure 6 - Daisy Chain Connection
8
* 120-Ohm Termination
AD1273
S
W B
W B
W B
AD1273
*
AD1273
S
W B