Crown I-Tech I-T4000, Operation Manual

Page: 40 / 52

Operation Manual
I-Tech Series Power Amplifiers
page 40
8.1 Protection Systems
Your Crown amplifier provides extensive pro-
tection and diagnostic capabilities, including
thermal level control, fault indicators, high-
pass filtering, DC protect, AC under/over volt-
age protection, inrush limiting, and variable-
speed fans.
8.1.1 Thermal Level Control (TLC)
If the amplifier 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 amplifier 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
amplifier shut down, and only occurs in
extreme situations.
8.1.2 Circuit Breaker
If the current draw of the amplifier 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
amplifier 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 or meet all specs on 100V - 240VAC,
50/60 Hz.
Crown’s Switching Power Supply minimizes the
amplifier’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
operate with a much smaller (and lighter) trans-
former because they first convert the AC up to a
much higher frequency, thereby reducing
waste.
Power Factor Correction (PFC) controls how
your amplifier 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 Amplifier)
Interleave technology allows high levels of
power output without all the associated heat
found in a conventional amplifier. This highly
efficient 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.
8.5 Rear Rack Ears with Integral
EZ-Rack Pin
The rear rack ears have a built-in EZ-Rack Pin
for easier installation.