EDWARDS SYSTEMS TECHNOLOGY AA75 Series User manual

AA75 Series Audio Amplifiers
Installation Manual
P/N 270218
Revised 14JUL97
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DEVELOPED BY Edwards Systems Technology
6411 Parkland Drive
Sarasota, FL 34243
[phone]
COPYRIGHT NOTICE Copyright © 1997 Edwards Systems Technology, Inc.
This manual and the products it describes are copyrighted by
Edwards Systems Technology, Inc. (EST). You may not reproduce,
translate, transcribe, or transmit any part of this manual without
express, written permission from EST.
This manual contains proprietary information intended for distribution
to authorized persons or companies for the sole purpose of
conducting business with Edwards Systems Technology, Inc. If you
distribute any information contained in this manual to unauthorized
persons, you have violated all distributor agreements and we may
take legal action.
CREDITS This manual was designed and written by the EST Technical
Services - Documentation Department, Sarasota.
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Content
Description 1
Specifications 3
Installation 4
Mechanical Assembly 4
Model AA75-25 5
Model AA75P-25 7
Model AA75T-25 9
Operation 13
Model AA75-25 Amplifier 13
Model AA75P-25 Amplifier 13
Model AA75T-25 Amplifier 14
Wiring Methods 15
Amplifier Signal Flow Diagrams 16
Application Drawings 18
Dual-Channel Audio System Configuration 18
Single-Channel Audio System Configuration 19
Single-Channel Audio System Configuration With SIGA-CC1
Module 20
AA75 Amplifier Backup Using “B” Riser 21
AA75 Amplifier Backup Using ARA-1 Relay 22
AA75 Amplifier Backup Per IRC-3 Enclosure 23
Remote Paging 24
Maintenance and Troubleshooting 25
AA75 Series Audio Amplifiers Manual i
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Important information
Limitation of liability
The content of this manual is proprietary in nature and is intended
solely for distribution to authorized persons, companies, distributors
and/or others for the sole purpose of conducting business associated
with Edwards Systems Technology, Inc. The distribution of
information contained within this manual to unauthorized persons shall
constitute a violation of any distributor agreements and may result in
implementation of legal proceedings.
This product has been designed to meet the requirements of NFPA
Standard 72, 1996 Edition; Underwriters Laboratories, Inc., Standard
864, 7th Edition; and Underwriters Laboratories of Canada, Inc.,
Standard ULC S527. Installation in accordance with this manual,
applicable codes, and the instructions of the Authority Having
Jurisdiction is mandatory. EST, Inc. shall not under any circumstances
be liable for any incidental or consequential damages arising from loss
of property or other damages or losses owing to the failure of EST, Inc.
products beyond the cost of repair or replacement of any defective
products. EST, Inc. reserves the right to make product improvements
and change product specifications at any time.
While every precaution has been taken during the preparation of this
manual to ensure the accuracy of its contents, EST assumes no
responsibility for errors or omissions.
FCC warning
This equipment can generate and radiate radio frequency energy. If this
equipment is not installed in accordance with this manual, it may cause
interference to radio communications. This equipment has been tested
and found to comply within the limits for Class A computing devices
pursuant to Subpart B of Part 15 of the FCC Rules. These rules are
designed to provide reasonable protection against such interference
when this equipment is operated in a commercial environment.
Operation of this equipment is likely to cause interference, in which
case the user at his own expense, is required to take whatever measures
may be required to correct the interference.
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Document history
AA75 Series Auido Amplifiers Installation Manual P/N 270218
Revision Status
Revision Date Reason For Change
1.0 September 1995 Initial Release.
1.5 July 1997 Layout and content revisions.
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iv AA75 Series Audio Amplifiers Manual
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Description
The AA75 series of audio amplifiers are solid state magnetic coupled
amplifiers designed for use in the life safety industry. Three models are
available to meet various applications.
1. The AA75 is a 50 watt amplifier used for distributive amplifier
application.
2. The AA75P contains a paging microphone and tone generator and
may be used in conjunction with the above amplifiers for paging
applications.
3. The AA75T contains a tone generator. May be used as a
supplemental back-up in the event primary tone generation is lost.
The amplifiers provide 50 Watts output and obtain their DC power
from the 24 VDC power supply source within the Fire alarm control
panel.
The AA75 series amplifiers are inherently power limited. If a short or
continuous overload is sensed, the output will be shut down and an
amplifier trouble relay is activated. The amplifiers contain three LED
status indicators. Two LED’s (green, red) are used to indicate the
correct gain setting (normal, too high, low) and the third LED (yellow)
is used to indicate an amplifier trouble.
The amplifiers may be used in conjunction with an existing paging
system containing a preamplifier and tone generators or may be used in
conjunction with EST’s Audio Control Panel, model ACP, ACP-6, or
FCCA-4/6.
Internal circuits are provided which allow automatic or manual
selection of one of two inputs which may be applied to the Audio
Amplifier. Applicable electronic control circuitry also allow for
applications requiring the addition of a message repeater such as EST
model RAMM-A or MVM.
These amplifiers are designed to provide audio distribution, paging,
and tone generation for small to medium systems; may also be used in
conjunction with existing UL Listed Fire Control Panels since they
contain integral tone generators, selectable for slow whoop, 1 kHz or
600Hz and a paging microphone.
AA75 Series Audio Amplifiers Manual 1
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AUDIO AMPLIFIER
FOR FIRE PROTECTIVE SIGNALING USE
NORMAL
TOO HIGH
INPUT LEVEL
AMPLIFIER TRBL
RED AND GREEN LEDS OFF
INDICATES INPUT LEVEL
TOO LOW.
HIGH VOLTAGE -Disconnect
primary and secondary
power before servicing.
WARNING
MODEL AA75-25
Refer to manual 250046 (May '88)
for complete electrical ratings
and installation diagram.
EDWARDS S YSTEMS TECHNOLOGY
TM
[AA75-001.CDR]
Model AA75-25
AUDIO AMPLIFIER
FOR FIRE PROTECTIVE SIGNALING USE
NORMAL
TOO HIGH
INPUT LEVEL
AMPLIFIER TRBL
RED AND GREEN LEDS OFF
INDICATES INPUT LEVEL
TOO LOW.
HIGH VOLTAGE -Disconnect
primary and secondary
power before servicing.
WARNING
MODEL AA75P-25
Refer to manual 250046 (May '88)
for complete electrical ratings
and installation diagram.
EDWAR DS SYST EMS TEC HNOL OGY
TM
[AA75-002.CDR]
Model AA75P-25
AUDIO AMPLIFIER
FOR FIRE PROTECTIVE SIGNALING USE
NORMAL
TOO HIGH
INPUT LEVEL
AMPLIFIER TRBL
RED AND GREEN LEDS OFF
INDICATES INPUT LEVEL
TOO LOW.
HIGH VOLTAGE -Disconnect
primary and secondary
power before servicing.
WARNING
MODEL AA75T-25
Refer to manual 250046 (May '88)
for complete electrical ratings
and installation diagram.
EDWARDS SYSTEMS TE CHNOL OGY
TM
[AA75-003.CDR
]
Model AA75T-25
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Specifications
Specifications
Mechanical Specifications
Dimensions (HWD):
Inches (mm) 5.5 x 10.5 x 4 (140 x 267 x 102)
Weight (lb.):
AA75 Series
AA75P Series
AA75T Series
3.75
4.5
3.75
Operating Environment Temperature:
°F
°C
Humidity
32 - 120
0 - 49
85%
Electrical Specifications: AA75-25
Operating frequency 550Hz - 4KHz
Audio Power Output:
Voltage (rms)
Watts (max)
25
50
Distortion @ 1Khz (full load) <2%
Preamp Output (75P and 75T series ONLY):
Vrms
Max Load impedance
Amplifiers per preamp
1 Vrms
18 Ohms
50 (max.), 25 without a DAPM
Signal Inputs:
Channel 1
Input Impedance
Max. signal level (Vrms):
J1 OFF
J1 ON
Channel 2
Input Impedance
Max. signal level (Vrms)
J1 OFF
J1 ON
Auxiliary
Input Impedance
Max. signal level (Vrms):
J1 ON/OFF
900 Ohms
1
0.125
900 Ohms
1
0.125
900 Ohms
6 - 8 (Requires DAPM-R on the input)
Input power* (Standby)
Voltage (24Vdc)
Current
Full load current
Max ripple
24 Vdc
250 mA
3.44 A
3 V
Fail relay contacts:
Voltage max
Current max (resistive)
30 Vdc
500 mA
AA75 Series Audio Amplifiers Manual 3
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Installation
Mechanical Assembly
The following figure illustrates the amplifier mounting location when
EST cabinet #240075 is used. This cabinet is a surface mount unit with
key lock front door.
AA75 SERIES
AMPLIFIER
CONTROL MODULE
CM1(N) - CM2(N)
POWER SUPPLY
PS4/8B
GROUND STRAP
[AA75-010.CDR]
CAB 3 Setup
The following illustrates the mounting hardware for this type of
installation.
AMPLIFIER COVER
AMPLIFIER
PART OF CAB2/3/6
#6 SCREWS
[AA75-011.CDR]
Mounting Hardware
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Model AA75-25
Refer to the drawing below for the terminal nomenclature and
component locations for amplifiers without a paging microphone.
CHANNEL 1 CHANNEL 2
SHLD SHLDCH1/2 COM
AUX ACT
ACTIVATE IN/OUT
+
+
1
1
IN
RED
AMB
GAIN
ADJ.
J1
J2
GRN
AUXI LARY IN PU T FAIL/NOTIFY
IN SHLD
2
2
3
3
4
4
5
5
6
6
TB2 CB-1
TB1
P3
INPUT POWER
CONNECTOR
TB3
7
8
9
10
SHL D SHLDAUDI O AUD IO OUTRTN
+
-
-
+
PREAMP
CARD
[AA75-004.CDR]
Model AA75-25
TB1
Pre-amp Channel 1 (TB1-1 - TB1-3): Input to the audio amplifier.
Typically connected to the channel one preamp riser.
Pre-amp Channel 2 (TB1-4 - TB1-6): Input to the audio amplifier.
Typically connected to the channel two preamp riser.
Ch1/Ch2 Select (TB1-7): A contact closure to terminal TB1-8 will
select the Channel 2 preamp riser for amplification. No connection to
this terminal will select channel one riser for amplification.
Common (TB1-8): Power supply common.
Aux Activate (TB1-9): Not used.
Activate I/O (TB1-10): Not used.
P3
DC Input (24 VDC input): Input power must be supplied from a
PS4/8B or APS4/8B.
Note: When an APS8B or PS8B supply is used. The second 24 VDC
output on the supply cannot be used.
TB2
Aux Input (TB2-1 - TB2-3): Not used.
Fail/Notify (TB2-4 - TB2-6): Form C contacts that transfer when an
internal amplifier fault prevents Audio Power Output, or amplifier has
no power; contacts are shown energized.
AA75 Series Audio Amplifiers Manual 5
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TB3
Audio Output (TB3-1 - TB3-3): Origination of the Audio riser.
Audio Return (TB3-4 - TB3-6): If the audio riser is returned to this set
of terminals, open and short riser supervision will be provided.
Setup
The following options must be selected and/or setup during the
installation of each amplifier. Refer to the diagram below for preamp
card component locations and to the chart on the next page for setup
procedures for the AA75 series amplifiers.
LD1
GRN
[AA75-005.CDR]
RED GAIN
ADJ.
AMB
LD2 LD3
JP1
INPUT LEVEL
ON=125 mvRMS
OFF=1VRMS
JP2
P1
SUPV.
ON=DISABLE
OFF=ENABLE
Preamp Card
Preamp Card Setup
Setup Card/Location Function
JP1 Preamp Card OFF- Selects 1 VRMS Level
ON- Selects 125 mVRMS Level
JP2 Preamp Card ON-Disable riser supervision
OFF-Enable riser supervision
Gain
Adjust
Preamp Card With 1Khz tone input connected to CH1
preamp input, adjust the gain pot until
the Green LED is ON and the Red is
OFF. Use a DVM on AC scale and
measure 25VRMS on the output riser.
Check under load conditions.
Model AA75P-25
Refer to the figure below for the terminal nomenclature and component
locations for amplifiers with integral page microphone and tone
generator.
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CHANNEL 1 CHANNEL 2
SHLD SHLDCH1/2 COM
AUX ACT
ACTIVATE IN/OUT
+
+
1
1
IN
RED
AMB
GAIN
ADJ.
J1
J1
J2
J3
J2
P2
MICROPHONE
GRN
AUXILARY INPUT FAIL/NOTIFY
IN SHLD
2
2
3
3
4
4
5
5
6
6
TB2
TB1
P3
INPUT POWER
CONNECTOR
TB3
7
8
9
10
SHL D SH LDAUDI O AUD IO OUTRTN
+
-
-
+
PREAMP
CARD
MICROPHONE
TONE CARD
[AA75-006.CDR]
CB-1
Model AA75P-25
TB1
Pre-amp Channel 1 (TB1-1 - TB1-3): Output from the internal tone
generator and paging microphone. This is the output or the origination
of the preamp riser. In systems with multiple amplifiers this output will
be connected to models AA75-25 amplifiers "Pre-amp Channel 1"
terminals.
Pre-amp Channel 2 (TB1-4 - TB1-6): Input to the audio amplifier.
Typically connected to the channel two preamp riser.
Ch1/Ch2 Select (TB1-7): A contact closure to terminal TB1-8 will
select the Channel 2 preamp riser for amplification. No connection to
this terminal will select the internal tone generator. When Channel 2 is
selected, it is NOT routed out to the pre-amp Channel 1.
Common (TB1-8): Same point as power supply common.
Aux Activate (TB1-9): A contact closure to TB1-8 (common) selects
the device connected to TB2-1 through TB2-3 (Aux input) to be
amplified upon activation instead of the internal tone generator. Aux
input pre-amp is routed to the pre-amp Channel 1.
Activate I/O (TB1-10): A contact closure to TB1-8 (common) changes
the output from supervisory tone burst to one of the selected tone
generators or a message repeater. This tone is also routed to the pre-
amp Channel 1.
P3
DC Input (24 VDC input): Input power must be supplied from a
PS4/8B or APS4/8B.
Note: When a APS8B or PS8B supply is used, the second 24 VDC
output on the supply must NOT be used for anything.
AA75 Series Audio Amplifiers Manual 7
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TB2
Aux Input (TB2-1 - TB2-3): Signal input from auxiliary device;
typically a message repeater or tape deck (RAMM-A or MVM).
Requires the use of a DAPM-R.
Fail/Notify (TB2-4 - TB2-6): Form C contacts transfer when an
internal amplifier fault prevents Audio Power Output, or when DC
power is lost to amplifier.
TB3
Audio Output (TB3-1 - TB3-3): Origination of the Audio riser.
Audio Return (TB3-4 - TB3-6): If the audio riser is returned to this set
of terminals it provides open and short riser supervision.
Setup
The following features and options must be selected or setup during the
installation of each amplifier. Refer to the following figure for
component locations on the preamp card to properly setup the models
AA75P series amplifiers.
LD1
GRN
[AA75-005.CDR]
RED GAIN
ADJ.
AMB
LD2 LD3
JP1
INPUT LEVEL
ON=125 mvRMS
OFF=1VRMS
JP2
P1
SUPV.
ON=DISABLE
OFF=ENABLE
Preamp Card
Preamp Card Setup
Setup Card/Location Function
JP1 Preamp Card OFF- Selects 1 VRMS Level
ON- Selects 125 mVRMS Level
JP2 Preamp Card ON-Disable riser supervision
OFF-Enable riser supervision
Gain
Adjust
Preamp Card With 1Khz tone input connected to CH1
preamp input, adjust the gain pot until
the Green LED is ON and the Red is
OFF. Use a DVM on AC scale and
measure 25VRMS on the output riser.
Check under load conditions.
8 AA75 Series Audio Amplifiers Manual
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Microphone Tone Card Component Locations
J1
J1 - ON, J2 - ON = 1KHz
J1 - ON, J2 & J3 - OFF = 600Hz
J1 - OFF, J3 - ON = SLOW WHOOP
J2 / J3
P1
[AA75-007.CDR]
P2
MICROPHONE TONE CARD
MICROPHON
E
Microphone Tone card
Microphone Tone Card Setup
Function J1 J2 J3
Slow Whoop OFF ---- ON
1K Hz ON ON ----
600 Hz ON OFF OFF
Model AA75T-25
Refer to the figure below for the terminal nomenclature and component
locations for amplifiers with integral page microphone and tone
generator.
CHANNEL 1 CHANNEL 2
SHLD SHLDCH1/2 COM
AUX ACT
ACTI VATE IN/OUT
+
+
1
1
IN
RED
AMB
GAIN
ADJ.
J1
J1
J2
J3
J2
GRN
AUXI LARY IN PU T FAIL/NOTIFY
IN SHLD
2
2
3
3
4
4
5
5
6
6
TB2
TB1
P3
INPUT POWER
CONNECTOR
TB3
7
8
9
10
SHL D SHLDAUDI O AUD IO OUTRTN
+
-
-
+
PREAMP
CARD
TONE CARD
[AA75-008.CDR]
CB-1
Model AA75T-25
AA75 Series Audio Amplifiers Manual 9
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TB1
Pre-amp Channel 1 (TB1-1 - TB1-3): Output from the internal tone
generator and paging microphone. This is the output or the origination
of the preamp riser. In systems with multiple amplifiers this output will
be connected to models AA75-25 amplifiers "Pre-amp Channel 1"
terminals.
Pre-amp Channel 2 (TB1-4 - TB1-6): Input to the audio amplifier.
Typically connected to the channel two preamp riser.
Ch1/Ch2 Select (TB1-7): A contact closure to terminal TB1-8 will
select the Channel 2 preamp riser for amplification. No connection to
this terminal will select the internal tone generator. When Channel 2 is
selected, it is NOT routed out to the pre-amp Channel 1.
Common (TB1-8): Same point as power supply common.
Aux Activate (TB1-9): A contact closure to TB1-8 (common) selects
the device connected to TB2-1 through TB2-3 (Aux input) to be
amplified upon activation instead of the internal tone generator. Aux
input pre-amp is routed to the pre-amp Channel 1.
Activate I/O (TB1-10): A contact closure to TB1-8 (common) changes
the output from supervisory tone burst to one of the selected tone
generators or a message repeater. This tone is also routed to the pre-
amp Channel 1.
P3
DC Input (24 VDC input): Input power must be supplied from a
PS4/8B or APS4/8B.
Note: When a APS8B or PS8B supply is used, the second 24 VDC
output on the supply must NOT be used for anything.
TB2
Aux Input (TB2-1 - TB2-3): Signal input from auxiliary device;
typically a message repeater or tape deck (RAMM-A or MVM).
Requires the use of a DAPM-R.
Fail/Notify (TB2-4 - TB2-6): Form C contacts transfer when an
internal amplifier fault prevents Audio Power Output, or when DC
power is lost to amplifier.
TB3
Audio Output (TB3-1 - TB3-3): Origination of the Audio riser.
Audio Return (TB3-4 - TB3-6): If the audio riser is returned to this set
of terminals it provides open and short riser supervision.
Setup
The following features and options must be selected or setup during the
installation of each amplifier. Refer to the following figure for
component locations on the preamp card to properly setup the models
AA75T series amplifiers.
10 AA75 Series Audio Amplifiers Manual
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LD1
GRN
[AA75-005.CDR]
RED GAIN
ADJ.
AMB
LD2 LD3
JP1
INPUT LEVEL
ON=125 mvRMS
OFF=1VRMS
JP2
P1
SUPV.
ON=DISABLE
OFF=ENABLE
Preamp Card
Preamp Card Setup
Setup Card/Location Function
JP1 Preamp Card OFF- Selects 1 VRMS Level
ON- Selects 125 mVRMS Level
JP2 Preamp Card ON-Disable riser supervision
OFF-Enable riser supervision
Gain
Adjust
Preamp Card With 1Khz tone input connected to CH1
preamp input, adjust the gain pot until
the Green LED is ON and the Red is
OFF. Use a DVM on AC scale and
measure 25VRMS on the output riser.
Check under load conditions.
Tone Card Component Locations
J1
J1 - ON, J2 - ON = 1KHz
J1 - ON, J2 & J3 - OFF = 600Hz
J1 - OFF, J3 - ON = SLOW WHOOP
J2 / J3
P1
TONE CARD
[AA75-009.CDR]
Tone Card
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Microphone Tone Card Setup
Function J1 J2 J3
Slow Whoop OFF ---- ON
1K Hz ON ON ----
600 Hz ON OFF OFF
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Operation
The operation of the model AA75, AA75P and AA75T series
amplifiers depend upon the connection of the control and signal inputs
to the amplifier. This section will only provide the basic operation of
the AA75 series amplifiers and how the different control inputs will
affect system operation.
Model AA75-25 Amplifier
In normal operation the preamp input signal at the PREAMP CH1 IN
terminals is amplified and provided as an output on the AUDIO RISER
OUTPUT terminals. Normally the signal at the Preamp channel 1
terminals is a supervisory tone generated by an AA75P/T-25 amplifier
or from an FCCA or an Audio Control Panel. The preamp input signal
being amplified is selected by contact closure controlling the CH1/2
SELECT terminal: terminal assignments are discussed in a later section
of this manual. The AUDIO OUTPUT terminals are connected to
multiple speaker circuits as shown in the applications section. The
audio riser is typically returned to the originating amplifier and
connected to the "AUDIO RETURN" terminals. The Audio Return
terminal supervises the audio riser and expects the 1 kHz (¼ second)
tone bursts which repeats approximately every 4 seconds. If the tone
burst is not received after a 15 second time-out period the amplifier
trouble contacts are activated. The supervisory signal detection may be
defeated by installing jumper JP2 on the preamp card.
Model AA75P-25 Amplifier
In normal operation the Tone/microphone card generates a supervisory
signal and outputs this signal to the "AUDIO OUTPUT" and PREAMP
CHANNEL 1 terminals. The AUDIO OUTPUT is the origination of a
50 Watt riser and the PREAMP CHANNEL 1 is the origination of the
preamp riser. The supervisory signal consists of a 1 kHz tone burst (¼
second) which repeats approximately every 4 seconds.
In the alarm condition the "ACTIVATE I/O" terminal must be
connected to common by the Fire Alarm Control Panel. When this
terminal is pulled low, the internal tone generator changes from the
supervisory tone to steady tone (1KHz or 600Hz) or the Slow-Whoop
tone, depending upon the setting of J1/J2/J3 on the Microphone/tone
card. If the AUX ACTIVATE terminal is connected to common the
device connected to the AUX INPUT will be amplified instead of the
tone generator signal. At any time during the Alarm condition live
voice paging may be accomplished by pressing the Push-to-talk switch
on the microphone. When paging is active the tone or Aux signal is
temporarily discontinued and a pre-alert tone is activated. After 5
seconds, the live voice signal is output to both the AUDIO riser and the
preamp riser.
AA75 Series Audio Amplifiers Manual 13
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Model AA75T-25 Amplifier
In normal operation the Tone card generates a supervisory signal and
outputs this signal to the "AUDIO OUTPUT" and PREAMP
CHANNEL 1 terminals. The AUDIO OUTPUT is the origination of a
50 Watt riser and the PREAMP CHANNEL 1 is the origination of the
preamp riser. The supervisory signal consists of a 1 kHz tone burst (¼
second) which repeats approximately every 4 seconds. The AUDIO
OUTPUT terminals are connected to multiple speaker circuits as
shown in the applications section. The audio riser is typically returned
to the originating amplifier and connected to the "AUDIO RETURN"
terminals. The Audio Return terminal supervises the audio riser and
expects the 1 kHz tone bursts. If the tone burst is not received after a
15 second time-out period the amplifier trouble contacts are activated.
The supervisory signal detection may be defeated by installing jumper
JP2 on the preamp card.
In the alarm condition the "ACTIVATE I/O" terminal must be
connected to common by the Fire Alarm Control Panel. When this
terminal is pulled low, the internal tone generator changes from the
supervisory tone to steady tone (1KHz or 600Hz) or the Slow-Whoop
tone, depending upon the setting of J1/J2/J3 on the Microphone/tone
card. If the AUX ACTIVATE terminal is connected to common the
device connected to the AUX INPUT will be amplified instead of the
tone generator signal.
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