General Precautions; Ac Power Requirements; Thermal Considerations; Rack Mounting - Mackie FRS-1300 Owner's Manual

General Precautions

AC POWER REQUIREMENTS

The amplifier's power cord should be plugged into an
AC outlet properly configured with the voltage required
for your particular model.
Be sure the AC outlet can supply enough current to
allow full power operation of all the amplifiers plugged
into it. The outlet should be a three-prong socket that
matches the power cord.
WARNING: Bypassing the plug's safety ground
pin can be dangerous. Don't do it!
The AC current demand of an amplifier varies depend-
ing on several factors, including the load impedance,
the crest factor, and the duty cycle of the program
material. Under typical conditions reproducing rock
music where musical peaks are just below clipping, the
amplifiers require the following average currents:
FRS•1300 = 6 A
FRS•1700 = 8 A
FRS•2800 =11 A
It is recommended that a stiff supply of AC power be
used because the amplifier places high current demands
on the AC line. The more power that is available on the
line, the louder the amplifier will play and the more
peak output power will be available for cleaner, punch-
ier bass.
If you have more than one amplifier sharing an AC
outlet, you should avoid turning them all on at the
same time. Rather, sequence them on, one at a time,
to prevent popping the circuit breaker (due to in-rush
current).

THERMAL CONSIDERATIONS

The power amplifier is fan cooled. Air is drawn
through the rear panel vents, to cool down the amplifier
heatsinks, and then expelled through the front panel
vents.
When installing, be sure to allow sufficient air space
around the front and rear of the amplifier for adequate
cooling for the heatsinks. Leave at least one rack space
above and below, and at least 6 inches behind and in
front of the chassis to allow proper ventilation.
If the amplifier should overheat, a thermal switch
turns off the power amplifier, allowing the heatsink
to cool down. Once the amplifier has cooled to a safe
operating temperature, the thermal switch resets and
reactivates the amplifier. If this should occur, identify
the cause of the problem and take corrective action. For
example:
• Provide better ventilation
• Install a fan in the rack to move more air
• Make sure the amplifier is not overloaded with
too low of a load impedance or by a short circuit
on the speaker line

RACK MOUNTING

The FRS amplifiers are designed to be mounted in a
standard 19 inch rack. They require two rack spaces
(2U = 3.5"). They also require 14.65" depth inside the
rack, including the rear support brackets. When design-
ing your rack, put the heavier items at the bottom and
the lighter items toward the top.
Secure the front panel of the amplifier to the front of
the rack using four screws with soft washers to prevent
scratching the panel. In addition, because of the weight
of the amplifier, you must secure the rear support brack-
ets of the amplifier to the back of the rack. You could
use a support rail or shelf across the back of the rack, or
angle brackets attached between the rear support rails
and the rear rails of the rack. This is recommended for
all components mounted in a rack that is going to be
moved frequently.

MAINTENANCE

Usually, your amplifier will not require regular main-
tenance for normal use. However, you can do several
things to keep it in good operating and cosmetic condi-
tion.
• Testing: Periodically test your system for
proper performance. A simple test is to play a
CD through it using well-defined, articulate,
wide-range program material. Listen to ensure
all drivers are working properly and for any evi-
dence of distortion or other extraneous sounds.
Test at several volume levels: very low, normal,
and high.
• Cleaning: Use only a clean dry cloth to dust off
and clean the surface. Turn off the power to the
amplifier while you do this.
Owner's Manual
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