wheelock ST-C8, ST-B4-1, ST-B4 INSTALLATION INSTRUCTIONS

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Long Branch, NJ 07740 Thank you for using our products.
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www.wheelockinc.com

INSTALLATION INSTRUCTIONS

PAGING SPEAKERS WITH 25V/70V TRANSFORMER

Use this product according to this instruction manual. Please keep this instruction manual for future reference.

MODELS: ST-B4, ST-C8, ST-C8V, ST-C8M AND ST-C8MV

DESCRIPTION:

Wheelock Paging Speakers are ready to be installed assemblies consisting of a loudspeaker, round white grille, and a combination
25V/70V line matching transformer. ST-B4 includes a plastic surface mount housing. ST-C8, ST-C8V, ST-C8M and ST-C8MV
include a round flush grille. ST-C8V and ST-C8MV include a recessed volume control. ST-C8 refers to all models for specification
and installation purposes. The volume attenuation will reduce output by 20dB.

The ST-C8 models are 8" ceiling mount speakers, used primarily in office areas, hallways and other low to medium noise level areas.
The ST-B4 is a 4" surface wall mount speaker used in the same areas, when it is not convenient to mount ceiling speakers.
The areas ambient noise level will determine the speaker power (volume) tap chosen for a specific installation. Table 1 shows typical
noise levels in various locations.

WARNING: 1) THESE DEVICES ARE NOT INTENDED FOR USE IN HAZARDOUS LOCATIONS AS DEFINED BY

THE NATIONAL ELECTRICAL CODE (NEC) AND BY THE NATIONAL FIRE PROTECTION ASSOCIATION (NFPA).

2) THESE DEVICES ARE DESIGNED FOR INDOOR USE ONLY. DO NOT EXPOSE TO RAIN OR MOISTURE.

Table 1: Typical Noise Levels

Location dB
Assembly Line 75
Supermarket 75
Transportation - --­ Waiting Room 75
Office (Noisy) 70
Shipping/Warehouse 70
Restaurant 70
Department Store 65
Bank (Public Area) 65
Office (Quiet) 55
Office/Doctors - --­ Waiting Room 55
Hotel Lobby 55
Doctors Exam Room 55

NOTE: The power taps chosen should result in the paging level exceeding the areas ambient noise level by at least 6dB, and the
background music level exceeding the ambient noise level by at least 3dB.

Copyright 1999 Wheelock, Inc. All rights reserved.

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Table 2: Specifications

Cone Diameter ST-C8 Models ST-B4 - 4"
Voice Coil Impedance 8 Ohms

Speaker Magnet Weight & Material 5.3 oz. Ceramic

Power Handling Capacity 6 Watts Nominal 5 Watts Nominal
(Program Material) 10 Watts Maximum 8 Watts Maximum
Shape Round Rectangular

Grille Size 12 5/8” Dia. x 3"D 5"W x 7 1/4"H x 2

3/4"D
Finish White Ivory
Material Plastic/Metal

Sound Pressure Level 1 meter 94dB 86dB

(on axis, @ 1W, @ 1 KHz) 4 feet 92dB 84dB

10 feet 84dB 76dB

Frequency Response 200 Hz - 14,000 Hz 200 Hz - 10,000 Hz

Volume Control Attenuation 20dB at any wattage tap

Not Applicable

(ST-C8V only)

Line Voltage 25V/70V Combination

Transformer Power taps 4W, 2W, 1W, 1/2W, 1/4W, 1/8W

Optional Backbox Recessed Surface

Mounting CBB-8 (backbox not required)

Accessories Speaker Support Bridge SSB-8 Not Required

APPLICATION INFORMATION:

A. ST-C8 MODELS CEILING MOUNT SPEAKERS

Ceiling mounted speakers should be spaced at a distance equal to twice the ceiling height. Because of their cone shaped sound

projection (dispersion), ceiling speakers cover more area as the ceiling height increases. These factors are illustrated in Tables 3
and 4, and Figure 1.

Table 3: Ceiling Speaker Spacing and Coverage

Table 4: Speaker Coverage in Square Feet - Ceiling Height (Feet)

Ceiling Speaker Coverage Per Speaker Number Of

Height (Ft.) Spacing (Ft.) (Square Ft.) Speakers 8 9 10 11 12

8 16 250 1 250 325 400 485 575
10 20 400 2 500 650 800 970 1,150
12 24 575 3 750 975 1,200 1,450 2,300

4 1,000 1,300 1,600 1,930 2,875
5 1,250 1,625 2,000 2,410 3,450
6 1,500 1,950 2,400 2,890 4,025
7 1,750 2,275 2,800 3,370 4,600
8 2,000 2,600 3,200 3,850 5,175
9 2,250 2,925 3,600 4,330 5,750
10 2,500 3,250 4,000 4,810 6,325

Figure 1: Ceiling Speaker Spacing and Coverage Figure 2: Typical Ceiling Speaker Layout

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