Yamaha RX-V730 Service Manual page 10

RX-V730/RX-V730RDS/RX-V630/RX-V630RDS
HTR-5560/HTR-5560RDS/DSP-AX630/DSP-AX630SE
Cause: An excessive current flowed through the power
amplifier.
Supplementary information: As current of the power
transistor is detected, the abnormal channel can be
identified by checking the current detect transistor.
Turning on the power without correcting the abnormality
will cause the protection function to work immediately and
the power supply will instantly be shut off.
Note)
• Applying the power to a unit without correcting the
abnormality can be dangerous and cause additional
circuit damage.
• The output transistors in each amplifier channel
should be checked for damage before applying any
power.
• Amplifier current should be monitored by measuring
across the emitter resistors for each channel.
Cause: The voltage in the power supply section is
abnormal.
Supplementary information: The abnormal voltage is
displayed in % based on 5V as 100%.
Turning on the power without correcting the abnormality
will cause the protection function to work 1 second later
and the power supply will be shut off.
Cause: DC output of the power amplifier is abnormal.
Turning on the power without correcting the abnormality
will cause the protection function to work 3 seconds later
and the power supply will be shut off.
22
When there is a history of protection
function due to abnormal voltage in
the power supply section
Voltage display in %
When there is a history of protection
function due to abnormal DC output
Version (1 alphabet)
Version (1 alphabet)