40 Distributed Audio Panel Manual — P/N 52265:B1 6/8/2010
Installation Input Circuits
3.5.2 CMD Input Circuits
The Distributed Audio Panel has five Command Input circuits, which are used to activate the panel
amplifiers which, in turn, transmit an audio signal over the system speakers. All field wiring for
the circuits is power-limited and supervised for opens and ground faults. Note that a ground fault is
indicated when there is zero impedance to ground.
CMD1 and CMD2 Command Input circuits can be independently field programmed to be triggered
by a contact closure or by the reverse polarity of a Notification Appliance Circuit. (IMPORTANT!
When CMD1 and CMD2 are configured for reverse polarity, the NAC cannot be Coded). Input and
output terminals are provided for CMD1 and CMD2 to allow placement of the Distributed Audio
Panel anywhere along a Notification Appliance Circuit allowing nondedicated use of host FACP
NAC for triggering. CMD1 has relay contacts (maximum current 2.0 amps) before the out termi-
nals which will open the outgoing NAC circuit during a Distributed Audio Panel trouble condition.
This causes an NAC trouble at the host FACP. Note that CMD1 and CMD2 configurations can be
independently set so that both circuits are triggered by the same type of input or by different types
of inputs (see Figure 3.8 on page 40).
CMD1 is programmed for reverse polarity and CMD2 is programmed for contact closure. CMD3,
CMD4 and CMD5 Command Input circuits are triggered by a contact closure only.
3.5.3 Trouble Contact Input
The Trouble Contact Input is a nonsupervised, non-isolated input which can be used to monitor the
trouble contacts of remote battery chargers, power supplies, etc. The maximum contact closure
operation @ 30VDC current is 1.2 mA.
Figure 3.8 Command Input Circuits
Style Z (Class A)
FACP EOL Resistor
(for Style Y - Class B only)
NAC reverse polarity trigger
(alarm polarity shown)
Contact Closure trigger such as alarm contact
(4.7K, 1/4 watt EOL Resistors P/N: 27072)
Audio Distribution Panel
1 2 1 2 1 2
alarm polarity shown
- + + -
NOTE: Trouble Input is not suitable for AC Failure Report.