Fuses And Circuit Breakers; Advanced Features - Crown MA-1202 Operation Manual

MA Series Power Amplifiers

5 Advanced Features

and Options

5.1.4 Fuses and Circuit Breakers

The power supplies of the Macro-Tech 602 and
1202 are protected by fuses. The power sup-
plies of the Macro-Tech 2402 are protected by
circuit breakers. With rated loads and output
levels, the fuses (or circuit breakers) should
only shut down the amplifier in the rare
instance of a catastrophic failure. Other protec-
tion systems like ODEP keep the amplifier
operational under most other severe condi-
tions. The fuses (or circuit breakers) can also
shut down the amplifier in cases where
extremely low-impedance loads and high out-
put levels result in current draw that exceeds
their rating. Again, this should only be possible
when operating outside rated conditions, such
as when the amplifier is used to drive a 1-ohm
load in Stereo mode, or when a signal over-
loads the input and is clipped severely.
All 120 VAC, 60 Hz units and all Macro-Tech
2402s have a separate fuse for the low-voltage
power supply. All units have separate fuses or
breakers for the high-voltage power supplies.
Macro-Tech amplifiers do not blow their fuses
or trip their breakers unless something is
wrong. In the rare event that an internal fuse
blows, please refer the unit to a qualified tech-
nician. If a breaker in a Macro-Tech 2402 trips,
try to identify and correct the problem before
resetting the breakers with the back panel Reset
switches. If the problem persists, refer the unit
to a qualified technician.
5.2 Advanced Features
Macro-Tech amplifiers use cutting edge tech-
nology to deliver the ultimate in power and
value for their size, weight and price. They offer
numerous advantages over conventional
designs and provide benefits you can't get in
amplifiers from any other manufacturer.
Operation Manual
Here are some of their many features:
• Crown's Grounded Bridge design deliv-
ers large voltage swings without using
easily stressed output-transistor config-
urations like conventional amplifiers.
The results are lower distortion and
superior reliability.
• Patented ODEP (Output Device Emulation
Protection) circuitry compensates for
overheating and overload to keep the
amplifier working when others would
fail.
• IOC (Input/Output Comparator) circuitry
immediately alerts of any distortion
exceeding 0.05%, providing dynamic
proof of distortion-free performance.
• PIP (Programmable Input Processor)
connector accepts accessories that tailor
the amplifier to suit specific applications.
• Enhanced PIP2 (Programmable Input
Processor) connector accepts new
accessory modules that further tailor the
amplifier to suit specific applications,
including wideband load current moni-
toring.
• Two mono modes (Bridge-Mono and
Parallel-Mono) for driving a wide range
of load impedances.
• Very low harmonic and intermodulation
distortion result in the best dynamic
transfer function in the industry.
• High damping factor provides superior
control over low- frequency drivers for a
clean, accurate low end.
• Full protection against shorted outputs,
mismatched loads, input/output DC,
general overheating, high-frequency
overloads and internal faults.
• Dedicated power supply transformers
isolate channels in Stereo mode for
superb crosstalk characteristics and reli-
ability—each channel is virtually a sepa-
rate amplifier.
• Balanced inputs with internal three-posi-
tion sensitivity switch and adjustable
front-panel level controls.
• Full protection from shorted, open and
mismatched loads, general overheating,
DC, high-frequency overloads, and full
internal fault protection are provided by
our latest protection scheme: "Quad-
Mute."
• Efficient heat sinks and a self-contained
forced-air cooling system dissipate heat
quickly and evenly for extra amplifier
protection and greater power output.
• Extra rugged, extruded aluminum front
panel with ODEP and signal presence/
IOC indicators for each channel, and an
Enable indicator.
• Mounts in a standard 19-inch (48.3-cm)
equipment rack (units can also be
stacked).
• Three-Year, No-Fault, Fully Transferable
warranty completely protects your
investment and guarantees its specifica-
tions.
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