LV SYSTEM TENDER PA SYSTEM

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TECHNICAL SPECIFICATION FOR PUBLIC ADDRESS SYSTEM

1.1 Scope of Work

The scope of work under this head shall include designing supplying and installing of

Public Address System. The work under this system shall consist of furnishing all

materials, equipment’s and appliances and lab our necessary to install the said system,

complete with Speakers, Amplifiers, Mike and Zone selection Panel.

The PA System is designed to serve the multi purpose of playing music, making general

announcement or to transmit the fire tone under fire condition.

1.2 System Design

The Speakers shall be distributed in the entire floor and shall be configured in different

zones. The announcement can be made in zone wise or to all the speakers simultaneously

in ALL CALL mode. Fire Alarm shall be announced immediately on receipt of Fire signal

from the panel to all zones.

Glossary of Terms

1.3 Amplifiers

All amplifiers shall be mixing type for combining speech and music.

The power amplifiers shall have adequate continuous (RMS) power output to meet the

requirement of the configuration. The unit shall be capable of delivering the rated output

watts with less than 0.05% harmonic distortion in the design bandwidth. The amplifier

shall have a broad band frequency response of 20 Hz to 20 KHz. The output voltage and

impedance shall meet with the system requirements. Amplifiers shall be protected

against over loads and output shorts and a special thermal overload on the heat sink.

The distributed audio amplifiers shall be magnetically coupled switch mode type with

two input signal sources selectable manually or automatically by the fire alarm system.

Output wattage shall be as shown in the schedule of work or as required to meet the

needs of the PA system.

Power as well as audio amplifiers shall be mounted in suitable wall mounted / floor

standing enclosures.

1.3.1 Speakers

Speakers shall be especially designed for broadcasting high quality, integrated emergency

fire alarm signals and voice communications and approved by an appropriate authority

for use in such situations.

Speakers shall be ceiling or Column mounted as shown in the schedule of work and shall

be completed with mounting brackets accessories etc. Speakers shall be in wooden or

metal enclosures.

LV SYSTEM TENDER PA SYSTEM

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Speakers shall be of high efficiency yielding maximum output at minimum power across

200 – 12000 Hz frequency ranges. Speakers shall have a line-matching transformer for

direct connection to amplifiers with multiple taps. Speakers shall be mounted in a rugged

metal housing with vandal resistant grille if specified.

Speakers shall be interconnected in the zone configuration.

1.3.2 Zone Selection Panel

The user interface to the entire public address system shall be the Zone Selection Panel. It

shall be able to address 20 zones.

The Panel shall have one Microphone for announcements. The selection of announcement

is done through the Panel. The announcement/Fire tone can be made zone wise. The

Control Panel shall have individual zone selection switches as well as ALL CALL switch.

The Zone selection panel shall include a tone generator that shall serve the purpose of

generating a unique fire tone in case of fire.

1.4 P A System Wiring

PA system wiring shall be done with 2 X 0.75sq.mm cable in 19mm dia PVC conduit

including termination complete as required.

The speakers in each zone are connected in parallel and are connected to the respective

output. The cables from each zone are separately routed and terminated in the Panel.

1.5 Testing and commissioning

Entire PA system shall be tested to establish the following.

a) Functionality of the PA system

b) Combined systems shall be tested for the overriding feature for prioritizing fire

alarm and life safety requirements.

c) Acceptable audibility of the public address in all spaces and record sound pressure

levels of the Public address viz the ambient noise levels.

Chief Engineer (Operation) Signature of bidder Company’s Round Seal Date Place