Yamaha PA24 Owner's Manual - Troubleshooting
14
Troubleshooting
The following table lists the main causes of abnormal operation and the corrective measures required as well as the
protective circuit operation in each case.
Current Draw
PC9501N
PC6501N
PC4801N
Indicator
Possible Cause
Remedy
Protection Circuit
CLIP indicator lights up
There is a short at the
ampli
fi
er’s speaker outputs, the
speaker’s inputs, or in the
wiring.
Locate and remove the short.
The PC limiter circuit activates
to protect the power transistors.
The impedance of the connected
speaker is too low.
Use a speaker with a minimum
impedance of 4
Ω
(8
Ω
in Bridge
mode).
PROTECTION indicator lights
up
The heat sink temperature has
exceeded 90°C.
Check the ventilation around the
ampli
fi
er and improve the
air
fl
ow if necessary.
The thermal protection circuit
activates to protect the power
transistors.
A DC voltage of ±2 V or greater
was detected in the ampli
fi
er’s
output circuit.
Consult your dealer or a Yamaha
service center.
The output relay activates to
protect the speaker system.
Line Current (A)
Power (W)
Thermal Dissipation
100/120V
230/240V
In
Out
Dissipated
Btu/h
kcal/h
standby
0.08
0.04
5
0
5
17
4
idle
1.0
0.5
55
0
55
188
47
1/8 power
8
Ω
/ch
8.2
4.5
500
250
250
853
215
4
Ω
/ch
10.5
5.8
682
375
307
1050
264
1/3 power
8
Ω
/ch
16.8
9.2
1093
667
426
1450
367
4
Ω
/ch
23.7
13.0
1613
1000
613
2090
527
Line Current (A)
Power (W)
Thermal Dissipation
100/120V
230/240V
In
Out
Dissipated
Btu/h
kcal/h
standby
0.08
0.04
5
0
5
17
4
idle
1.0
0.5
40
0
40
137
34
1/8 power
8
Ω
/ch
5.4
2.9
375
188
188
640
161
4
Ω
/ch
6.9
3.8
500
275
225
768
194
1/3 power
8
Ω
/ch
11.4
6.3
820
500
320
1090
275
4
Ω
/ch
16.4
9.0
1183
733
449
1530
387
Line Current (A)
Power (W)
Thermal Dissipation
100/120V
230/240V
In
Out
Dissipated
Btu/h
kcal/h
standby
0.08
0.04
5
0
5
17
4
idle
1.0
0.5
40
0
40
137
34
1/8 power
8
Ω
/ch
3.6
2.0
253
125
128
435
110
4
Ω
/ch
6.2
3.4
444
200
244
834
210
1/3 power
8
Ω
/ch
8.5
4.7
612
333
279
952
240
4
Ω
/ch
15.0
8.2
1077
533
544
1860
468