User guide

Distributed Audio Panel Manual — P/N 52265:B1 6/8/2010 39
Auxiliary DC Power Output Connections Installation
3.4 Auxiliary DC Power Output Connections
The Special Application Auxiliary DC power output (35 mA @ 24 VDC) is power-limited, nonret-
table power suitable for powering control modules and End-of Line Power supervision relays. See
the Device Compatibility Document for compatible devices.
3.5 Input Circuits
3.5.1 Master Command Bus
The Master Command Bus Input circuit, when used with the ACC-25/50 Series, can be used to add
paging flexibility. All field wiring for each circuit is power-limited and supervised for opens and
ground faults. Note that zero impedance to ground will be indicated as a ground fault.
The Master Command Bus Input circuit is triggered by a reverse polarity signal such as the one
from the Master Command Output Bus on the ACC-25/50 Series. Master Command input and out-
put terminals are provided to allow connection to additional audio distribution panels.
When connecting the Master Command Output of ACC-25/50 Series to the Master Command Bus
Input of distributed audio panels, the wiring must be supervised by a 4.7K EOL resistor connected
across the out terminals of Master Command Bus Output on the last panel.
In Example 1 illustrated below, the Master Command bus is activated during paging, which routes
paging audio from the riser to the Distributed Audio Panel speakers.
The maximum line resistance from the main ACC-25/50 Series to the last Distributed Audio Panel
is 130 ohms (65 ohms per conductor).
Figure 3.6 Auxiliary Power Connection
Figure 3.7 Example 1 - Activating Multiple Distributed Audio Panels with Master CMD Output Bus
(Paging active polarities shown)
General or
Emergency All-
Call Paging
Master Command
Master Command
Voice Evacuation
Control Panel
Distributed Audio Panel
Distributed Audio Panel
audio riser
NOTE: The ACC-25/50DAZS uses the Zone System serial link for paging operations, therefore
Master Command Bus connections are only used with ACC-25/50DA panels.