Federal Signal Corporation ultravoice UV, Installation, Operation And Service Manual

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48
Maintenance
UltraVoice (UV)
4. To replace a defective driver, remove the 4 hex head 1/4-inch mounting bolts that
are holding the inspection plate. Make sure the flat washers and split washers
are not misplaced. Note the color and location of the wires going to the driver.
Remove the driver by turning it counterclockwise. Make sure that the male
threads are lightly greased, and then install the new driver. Reconnect the wires as
previously noted. Reinstall the inspection plate. Repeat resistance check above.
5. Test the siren to verify the driver was properly installed.
Checking the Signal
To check the signal operation, do the following:
1. When checking for proper control module output, unplug the terminal strip
connectors to the speakers (at the bottom of the backplane motherboard) to
eliminate output from the speaker array.
2. Activate each of the signals and observe the signal indicators on the control
module and the amplifiers.
3. If desired, you can connect an oscilloscope or digital multi-meter (DMM) to the
amplifier module output terminal strip to observe the amplifier output. This output
is at least 67 V
RMS
during a signal. To limit sound output, plug in one amplifier
terminal strip connector at a time during this test.
4. Plug all of the amplifier terminal strip connectors to enable amplifier outputs.
Checking the Battery
To check the battery, do the following:
1. The voltage of a fully charged set of batteries is approximately 27.2 Vdc, and
charger current is less than 2 A. The charger is set for 27.2 +/- 0.1 Vdc at room
temperature.
2. Load test the batteries per the manufacturer’s specifications.
3. Some batteries are equipped with a built-in hydrometer. When the hydrometer eye
is green, the battery is charged. If the eye is dark, the battery needs charging. If
the eye is light in color, the battery is low on fluid and needs to be inspected for
leaks. Maintain or replace the battery as recommended by its manufacturer; obey
local or state laws governing the disposal of lead-acid batteries.
4. Check the battery terminals for corrosion. Clean and grease connectors and
terminals, if necessary.