Difference Between Models

Figure 1-1. Audible alarm BZ-204( )IFSS-9(V).

1-9.

Description

The audible alarm is comprised of an outer and an inner

housing (fig. 1-1), the latter of which contains an

acoustical sounding device (speaker), a battery

(emergency power), electronic circuitry (power supply,

trickle charger, audio ramp generator and amplifier), and

associated interconnecting electrical hardware. The

double-housing configuration affords both weather-

resistant and tamper-secure characteristics for the

contents of the housing.

1-10. Acoustic Alarm Device

The acoustic alarm device is a 25 watt, 16 ohm, per-

manent magnet, submergence proof speaker. The

speaker is mounted to the back panel of the inner

housing. The mouth of the speaker horn is oriented

toward the acoustical port provided in the housing.

1-11. Power Supply

Ac input power is routed into the audible alarm

Figure 1-1. Audible Alarm BZ-204 () FSS-9(V)

1-13.

Tabulated Data

through a 3-terminal board strip (L1-1), a toggle switch

(ON-OFF) and a 0.5 ampere cartridge type fuse (tubular

Environmental conditions (operational)

fuseholder), into the ac power supply, dc battery trickle

Temperature range ....................... -20'F to 150°F.

charger and the audible ramp generator-amplifier

Humidity ........................ Up to 95 percent relative

package. An electronics package comprised of two,

Adverse weather..................................... All types

stack mounted printed circuit board assemblies in a

Environmental conditions (non-operational)

removable chassis is located in the lower right area of

Temperature range .......................-30°Fto 1650F.

the inner enclosure. The package provides circuitry for

Humidity ....................... UP to 95 percent relative

part of the power supply and the audio generator-

Shock .......................... 20 gs, 11 ms duration and

amplifier. The power transformer is located at the lower

bench handling

left within the inner enclosure. A 24-volt, 2.5 amp-hour,

Vibration ....................... Transportation conditions

immobilized electrolyte, hermetically sealed battery

Weight (with battery in-

provides the emergency backup power for the audible

stalled) ............................................. 29.5 pounds

alarm. The battery is mounted within and along the left

Dimensions

side of the inner housing. The battery weighs 6.0

Height............................................. 15 1/4 inches

pounds.

Width ........................................... 12 9/16 inches

Depth ............................................. 6 5/16 inches

Color

1-12.

Difference Between Models

Housing ............................. Gray per Federal Std.

595, color chip 26492.

The information in this manual applies to all audible

Power requirement

Primary power ............................... 115-volts -a.c.

alarm units beginning with Serial Number 0001. All

Secondary power.................................... 24 V dc.

units are physically and functionally the same, with all

Alarm ........................................................... 145 dB.

components being interchangeable.

1-2