QSC PowerLight Series, Техническое и сервисное руководство

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22 QSC Audio Products, Inc.
TD-000083-00
4. Turn off the fixture’s AC switch. Turn down the Variac to zero.
Turning off the fixture’s AC switch will automatically bleed the
capacitors down. Disconnect the module from the test fixture
and set the AP workstation back to sine wave and 0 volt RMS.
2.5 AC voltage conversions
WARNING: Regulatory agencies require that any operating
voltage conversions from 120 volts to any other voltage be done
only by QSC’s factory service. Any other operating voltage
conversions may be done only by a QSC-authorized service center
or international distributor.
The power supply modules and line filter modules in the
PowerLight 6.0 II, PowerLight 6.0
PFC
, and PowerLight 9.0
PFC
are
made for specific AC line voltages; they cannot be converted from
one to another. To convert an amplifier from120 to 230 volts AC or
vice-versa requires replacing both power supply modules and the
AC line filter. For this reason, it is seldom economically justifiable
to convert one of these models.
2.6 Bias adjustments
These three amplifier models have a trimpot for bias adjustment
on each audio channel. However, adjusting it is far more complex
than on most amplifiers, so it should only be done when working
on the module at board level, or as an emergency measure if the
module is running too hot at idle.