Federal Signal Corporation MODULATOR Series, Инструкция по установке и обслуживанию

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3-2
Therefore, for a person to hear a
warning signal in an industrial area,
the sound level intensity of that signal
must also be at least 90dB. In this
situation, any point receiving a signal
having less than 90dB intensity is
considered to be outside the effective
range of the siren.
In business districts an ambient
noise level of 80dB is common, and in
residential areas, 68dB of ambient
noise is typical. Assuming a 10dB loss
per distance doubled and a 68dB
minimum sound level, the effective
range of the MOD6024 is
approximately 3900 feet.
Wind speed and direction often
affect the propagation of sound from
the siren. Consequently, the direction
of the prevailing wind may also be a
factor to consider when selecting the
installation site(s) of a small, one or
two-siren system. For example, if the
prevailing wind is from the west, it
may be desirable to install the siren
toward the western edge of the area to
be covered.
Other factors to consider before
selecting the installation site include
the availability of electrical power, the
ease of installation and maintenance,
the height of surrounding
obstructions, and security against
vandalism.
The Modulator Controller (MCP)
comes with an optional and phase-
phase option (turbo mode) which can
increase the sound level output by 3db
in one of two directions (180
°). When installing the Modulator with this option it should be mounted in the
direction of the arrow on the mounting base, or the 1” fitting at the base of the siren.
3-2. SIREN INSTALLATION.
A. General.
Most siren installations are
one of two types: Pole Mount or Flat
Surface Mount. These two
configurations make it possible to
install a siren in almost any situation.
If the installations in this paragraph
are not suitable, modification of one of
the configurations may be practical.
A siren is typically installed
40 - 50 ft. above the ground. If the
installation is located less than 50 ft.
above the ground, the sound intensity
at close range may increase, but at the
same time the effective range of the
siren may be reduced. Conversely, if
the siren is located more than 50 ft.
above ground, the effective range of
the siren may increase, but the sound
may skip over areas closer to the
siren. These variables may make it
desirable to test the sound coverage of
the siren at various heights and
locations whenever possible.
B. Pole Mounting.
A typical pole-mounted siren
installation is shown in figure 3-1. The
siren is mounted on a Class 2 utility
pole (ANSI type wooden pole or
equivalent) with a minimum
horizontal ground stress rating of
3,700 pounds (1682 Kg). (Insure that
soil loads will conform to this size
utility pole). It is attached to the pole
by means of legs, as shown in figure 3-
2.
Using the 3 ft. long angle
iron legs, the siren is mounted on the
Class 2 utility pole as follows:
1. Uncrate the siren and
remove the nuts that hold the siren on
the shipping base. Lift the siren
approximately 3-1/2 ft. with a crane or
hoist.
2. Install the four legs on
the siren mounting plate, as shown in
figure 3-2. Use two 1/2" bolts, nuts and
lockwashers (provided) for each leg.
Do not tighten the bolts completely.