Crown Audio I-T12000 HD Stereo Amplifier User Manual


 
Operation Manual
I-Tech HD Series Power Ampli ers
page 48
8.1 Protection Systems
Your Crown amplifi er provides extensive
pro tection and diagnostic capabilities, including
thermal level control, fault indicators, high-pass
fi ltering, DC protect, AC under/over volt age
protection, inrush limiting, and variable-speed
fans with tachometer feedback. Microprocessor
monitors fans, and signals an error via System
Architect if fans are not operating.
8.1.1 Thermal Level Control (TLC)
If the amplifi er becomes too hot for safe
opera tion, the TLC will engage the input
compressor and the clip LED will illuminate. By
compress ing the input, the amplifi er will not
generate as much heat and will have a chance to
cool down. The degree of compression is
proportional to the amount of overheating. This
feature allows the show to go on, rather than
having the amplifi er shut down, and only occurs
in extreme situations.
8.1.2 Circuit Breaker
If the current draw of the amplifi er exceeds safe
limits, this breaker automatically disconnects the
power supply from the AC mains.
8 Advanced Features
8.2 Global Switching Power Sup ply
with PFC
Thanks to its global power supply, the I-Tech
amplifi er works anywhere in the world. There’s
no need to reset an AC mains voltage switch,
and no need to order a special model. The amp
will work and meet all specs on 100V - 240VAC,
50/60 Hz.
Crown’s Switching Power Supply minimizes the
amplifi er’s weight.
Typical non-switching power supplies require
large, heavy transformers in order to produce
the required power at the output stage. These
transformers must be large to operate at 50 to
60 Hz (standard AC supplied by the power
company).
By contrast, switching power supplies can oper-
ate with a much smaller (and lighter)
trans former because they fi rst convert the AC up
to a much higher frequency, thereby reducing
waste.
Power Factor Correction (PFC) controls how
your amplifi er draws current from the AC mains.
Instead of drawing high-magnitude cur rent
spikes that reduce the capacity of your power
distro (and couple noise into other sys tem
components), PFC draws a smooth and quiet
current waveform that is in phase with the mains
voltage waveform. PFC allows you to reduce the
size and weight of your power distri bution and
improve the performance of your signal
processors.
8.3 3rd Generation Class I Cir cuitry
Class I (BCA, Balanced Current Amplifi er)
Interleave technology allows high levels of
power output without all the associated heat
found in a conventional amplifi er. This highly
effi cient design also provides accurate,
uncol ored sound with very low distortion and a
high damping factor for tight, clean bass
response. And it can deliver more power to
reactive loads than conventional dissipative
designs (com fortably driving the latest high-
technology transducers). Class I also reduces
current draw of the AC mains, providing energy
conserva tion.
8.4 Color-Coded Rear Overlay
The labels on the rear panel are color coded to
group similar functions under common colors.