Edwards 3-ASU Assembly instructions

© 2013 UTC Fire & Security. All rights reserved. 1 / 6 P/N 270482 • REV 06 • REB 18JAN13
3-ASU and 3-ASU/4 Audio Source Unit
Installation Sheet
Description
The 3-ASU and 3-ASU/4 provide controls for emergency
paging. The 3-ASU/4 also provides a four-slot rail for installing
local rail modules.
Both units can store and play back prerecorded messages and
have inputs for connecting remote microphones and MN-FVPN
VoIP Encoder/Decoder modules.
The 3-ASU and 3-ASU/4 require one chassis space in an
enclosure. The 3-ASU includes a filler plate that mounts on the
cabinet inner door to prevent access to the electronics.
Installation
WARNING: Remove all sources of power from the cabinet
before installing or removing components. Failure to do so may
result in serious injury or loss of life.
1. Attach the chassis to the backbox using the hardware
provided. Align the backbox mounting studs with the holes
indicated in Figure 1.
2. Attach the ASU to the chassis using six 6/32 x 3/8 pan
head screws. Press the RCIC card onto the PEM studs.
See Figure 2.
3. Connect the ribbon cable (P/N 250195-01) between the
ASU card and the RCIC card.
4. If used, install the 3-ASUMX memory card. Make sure the
write protect switch is in the “off” or “write enabled”
position.
5. Connect the RCIC card to the other chassis rail
assemblies. See Figure 6 or Figure 7.
6. Plug the ribbon cable (P/N 250194-00) from the 3-ASU
cover assembly into J3 on the ASU card. See Figure 3.
7. Lift the 3-ASU cover assembly onto the chassis mounting
studs then attach it with the locknuts provided in the
hardware kit. See Figure 4.
Figure 1: Chassis mounting diagram
Note: 3-ASU/4 chassis shown.
Figure 2: Circuit board mounting diagram
Note: 3-ASU chassis shown.

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Figure 3: Cover installation
Note: 3-ASU/4 chassis shown.
Figure 4: Installation complete
Note: 3-ASU/4 chassis shown.
Wiring
Wire the 3-ASU and 3-ASU/4 as shown in Figure 5, Figure 6,
and Figure 7.
Notes
•All wiring is supervised and power-limited.
•If a 3-RS485 card is not installed, connect AUDIO DATA
PRIMARY on the ASU card to AUDIO A OUT on the
3-CPUx card. See Figure 5.
If a 3-RS485 card is installed, connect AUDIO DATA
PRIMARY on the ASU card to AUDIO A IN on the 3-CPUx
card.
•Wiring from a 3-REMICA or 3-REMICP must be shielded
and enclosed in conduit. See Figure 5.
•All shields must be continuous and insulated from ground,
except at the originating panel.
•The REMOTE input is for MNEC applications only. Not for
supplemental use.
Figure 5: ASU card wiring diagram

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Figure 6: 3-ASU RCIS card wiring diagram

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Figure 7: 3-ASU/4 RCIC card wiring diagram

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Specifications
Voltage
24 VDC
Current
Standby
Alarm
80 mA
80 mA
Ground fault
impedance
0.1 Ω
Wire size
22 to 12 AWG (0.5 to 2.5 mm²)
Dimensions
12.0 x 19.0 x 5.25 inches
(30.48 x 48.26 x 13.34 cm)
Mounting
One chassis space
Audio channels
8 simultaneous
Audio inputs
Local microphone (isolated and supervised)
Remote microphone (isolated and
supervised)
Firefighter's telephone (isolated and
supervised)
Remote audio (isolated and supervised)
Prerecorded message
storage
Two minutes expandable to 100 minutes with
optional 3-ASUMX/nn memory card
Operating environment
Temperature
Humidity
32 to 120°F (0 to 49°C)
0 to 93% RH, noncondensing at 90°F (32°C)
Contact information
For contact information, see www.edwardsutcfs.com.

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