User guide

C475 User Guide Version 1.0 5
Always operate the unit with the AC ground wire connected to the electrical system ground.
Precautions should be taken so that the means of grounding of a piece of equipment is not defeated.
Do not remove the lid. Removing the lid will expose you to potentially dangerous voltages. There are
no user serviceable parts inside.
Mechanical
To ensure that this equipment performs to specification, it should be mounted in a suitable rack or
enclosure as described below. Like all high power amplifiers, it should be kept away from other
equipment which is sensitive to magnetic fields or RF radiation. Also, this amplifier may suffer a
substantial reduction in performance if it is subjected to, or mounted close to, equipment which
radiates high RF fields, such as power transmitters.
When mounting the amplifier in a rack or enclosure, ensure that:-
1. The rear of the unit is adequately supported. The brackets which are supplied fit standard 19
inch (483mm) rack mounting systems. The front panel is not capable of supporting the front
panel is not capable of supporting the unit on its own.
2. There is adequate ventilation. The cooling fans suck cool air in through the front and blow hot
air out at the rear of the unit through the ventilating grills. If the air is not allowed to escape,
overheating will occur. Take care when mounting other equipment in the same rack.
3. The rack unit has a separate earth connection (technical earth).
Also see maintenance section page 9
EMC (RF Emissions)
The high frequency resonant converters in the C Series amplifiers have been designed to have very
low radio frequency (RF) emissions, which can cause interference with other equipment. In order to
reduce the influence of this, Power Amplifiers should be mounted in a dedicated metal rack
enclosure, which does not include equipment which may be sensitive to RF radiation, such as radio
microphone receivers.
GENERAL INFORMATION
Your C475 power amplifier utilises proprietary designed load impedance sensing output circuitry,
which enables the amplifier to drive the high voltage swings associated with speaker impedances of 8
ohms and above, but automatically switches to a high current/medium voltage output required by 4
ohm loads.
Fan speed is varied as required to keep the amplifier within its temperature limits. Signal limiters are
included to protect speakers from clipped signals.
The amplifier includes full DC and short circuit protection to ensure trouble-free service even in
‘harsher’ environments.