Troubleshooting guide

AUDIO INTERNATIONAL, INC. 10/97
10
Document #540056, Rev. IR, Model No.: PA-7500A
2.9.3 Remove power from the amplifier and verify that the 28 VDC emergency
power is supplied to the amplifier. Verify that the subwoofers are disabled
while emergency power is applied. Ensure that PA audio can be heard in
the speaker system from all respective microphones.
3.0 Operations
3.1 To operate the PA-7500A, load an audio source with selected material. Verify
that all of the audio inputs are available to the system and that selected audio
sources can be heard through the speaker system. All audio sources that interface
with this amplifier unit must be checked for proper operation. Use the switch
panel controls to verify that audio entertainment units are operating in a proper
manner.
3.2 Key and speak into a microphone and verify that the page / chime and briefer
overrides the entertainment audio. When a microphone key is activated, all other
audio source signals are overridden and PA audio should be present in the speaker
system.
4.0 Troubleshooting Guide
Problem Possible Cause Solution
No sound PA-7500A is improperly
installed.
Verify 28 VDC power and audio
input is present
Contact AI for assistance
5.0 Specifications and Drawings
5.1 Amplifier Unit Specifications
Physical Specifications
Housing Lightweight Aluminum
Dimensions Length-8.8”, width-4.9”, height-2.0”
Weight 3.2 lbs.
Electrical Specifications
Power 28 VDC @ continuous power output (2 channel)
Emergency Power 28 VDC Page / Chime
Data Bus Type RS-485
Audio Specifications
Electric Crossover Low Range: 135 Hz
High Range: 135 Hz
Channel Output Power 4-Channel 100 Watts Peak Output
Maximum per Channel
Minimum Load Impedance
4 Ω per Channel
Input Impedance 10K Briefer, 1VRMS (nominal)