Bogen AFDS2 Operation Manual

Automatic Failure Detector and Substitutor

AFDS2 Model

Installation and Use Manual

DESCRIPTION

The Bogen Model operation of the main and standby power amplifiers in a sound system. Should the main amplifier’s output level drop by as little as 2 dB, the AFDS2 substitutes the standby power amplifier.The changeover is nearly instantaneous with virtually no loss of signal.

The AFDS2 injects a set level of a supersonic frequency (40 kHz) into the inputs of the main and standby power amplifiers and continuously samples their outputs. If the 40 kHz level from either amplifier should fall below 2 dB*, a fault alert tone will sound, indicating a failure. Front panel-mounted LEDs indicate whether the main amplifier or the standby amplifier failed. The fault alert tone may be silenced by momentarily pressing the Silence button; however, the LED will stay on for the duration of the malfunction.

The AFDS2 may be used in either 25V or 70V systems.Booster output may be balanced or unbalanced;but, in a balanced system, two accessory input isolation transformers (Model TL100) are required.

The AFDS2 input impedance from the audio source is 10,000 ohms. In applications where the pre-amplifier is located away from the amplifier, the AFDS2 input can be converted to 600 ohms with the accessory WMT1A Line-Matching Transformer. Screwdriver-adjustable controls for setting the oscillator level and the detector sensitivities are provided on the rear panel.

The AFDS2 operates from a

ew terminals and RCA connectors on the rear chassis.The unit has a standard 19-inch wide panel,

at scr and is suitable for either rack or cabinet installation.

* Threshold is adjustable

AFDS2,Automatic Failure Detector and Substitutor,is an electronic unit which continuously supervises the

120V AC/60 Hz or 12V DC source. Line power consumption is 15W. All connections are made

is 3

1/2-inches high

PACKAGE CONTENTS

• Automatic Failure Detector & Substitutor unit

• Installation and Use Manual

TECHNICAL SPECIFICATIONS

Supervision Frequency: 40 kHz Supervision Frequency Level: 5mV to 50mV into 47k ohms Input Impedance: 10k ohms Detector Input Signal: 2V @ 40 kHz Detector Supervision Range: 2 dB (min.) to 12 db (max.) Failure Indicators: LEDs (visual) and tone module (aural) Controls: Screwdriver-adjustable controls for oscillator level and detector sensitivity Remote Annunciation: Status terminal provides 12V DC/500mA in the failure mode Operating Power Consumption: 120V AC, 15W, or 12V DC @ 0.5A Dimensions: 19" Weight: 8 lb. Accessories: T

the input fr

Temperatures:14°F to

W x 3

1/2" H x 7-1/2" D

100 transf

om a 600-ohm balanced line

ormers f

°F (-10°C to 65°C)

149

or 25V or 70V balanced systems;

WMT

1A Line-Matching

ormer to match

ransf

EQUIPMENT CONNECTIONS

AC Power Connections: The AC line cord has a three-prong plug which should be plugged into a three-wire grounded

120V, 60 Hz outlet.This will automatically ground the chassis.

Auxiliar

nected to the EXT PWR terminal on the chassis and the negative lead to the GND terminal. Input Connections: The input impedance of the AFDS2 is 10,000 ohms, accepting any unbalanced input capable of supply-

ing a signal at least 10% greater than that needed to drive the power amplifiers (which must have an input impedance of 10,000 ohms or gr input fr

System Connections: Single-conductor should be as short as possible. The remaining connections can be made with either double-conductor shielded wire or #20AWG hookup wire.

Note: Input cables should be r

y DC

visions are incorporated for mounting an accessory Model WMT

eater).

om a 600-ohm balanced line

outed separ

The unit ma

ately fr

om output cables

y be po

pacity shielded wire should be used for all input connections.These leads

w ca

ower Connections:

ered from the

12V

y. The positive lead must be con-

suppl

1A transf

ormer to match the

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