NAMES AND FUNCTIONS BASIC CONNECTIONS BASIC OPERATIONS ADVANCED CONNECTIONS ADVANCED OPERATIONS TROUBLESHOOTING
OTHERS
ENGLISH
TROUBLESHOOTING
7About the protection circuit
This unit is equipped with a protection circuit to protect the amplifier circuits and speaker system from damage.
If the protection circuit is activated, the sound is instantly muted. In this case, the message “PROTECT” flashes on the display panel, and the OPERATE indicator also flashes.
To deactivate the protection circuit, turn the unit off then back on again after about 1 minute or more.
¶At power on
For about 8 seconds after the power is turned on, the protection circuit is activated, muting the sound to give the amplifier circuits time to stabilize. Once the amplifier circuits stabilize, the protection circuit is released, and audio is enabled.
¶In the event of overcurrent
The protection circuit is activated if current exceeding a certain level is detected, which can happen if excessive signal flow is input to the amplifier or if the unit is connected to a speaker system of less than 4 Ω impedance. The protection circuit is also activated if a speaker cable shorts.
In such cases, the message “PROTECT” flashes on the display, and the volume is automatically reduced. After approximately 8 seconds, the protection circuit is released. Therefore, the volume needs readjusting to continue normal use.
If the overcurrent continues, the amplifier shuts itself OFF, and the OPERATE indicator flashes.
To deactivate the protection circuit, turn the unit off then back on again after about 1 minute or more.
¶If excessive ultrabass signals are input
The protection circuit is also activated if ultrabass signals are input. In such a case, the OPERATE indicator flashes, and the volume is automatically reduced. After approximately 8 seconds, the protection circuit is released. Therefore, the volume needs readjusting to continue normal use. If excessive ultrabass signal input continues or if DC voltage is detected owing to trouble with the amplifier, the amplifier shuts itself OFF, and the OPERATE indicator flashes.
To deactivate the protection circuit, turn the unit off then back on again after about 1 minute or more.
¶If the main-amplifier overheats
The protection circuit is activated if the temperature of the main- amplifier section rises above a certain level, which can happen if the amplifier is continuously used with excessive signal flow being input to it. The protection circuit is also activated when the specified operating temperature is exceeded, which can happen if the vents on top of the amplifier are covered or if the amplifier is installed on a cramped audio rack. In such a case, the OPERATE indicator flashes, and the volume is automatically reduced. After approximately 8 seconds, the protection circuit is released. Therefore, the volume needs readjusting to continue normal use.
If the temperature does not sufficiently fall within a certain amount of time after the protection circuit activation, the amplifier shuts itself OFF, and the OPERATE indicator flashes.
To deactivate the protection circuit, turn the unit off, let it stand until it cools down, then turn it ON again.
¶In the event of amplifier trouble
The protection circuit is activated, and the power is automatically shut OFF, if an abnormality is detected in the power circuit.The same happens if the main fuse inside the amplifier blows. In such cases, the OPERATE indicator flashes.
Turn the unit off then after several minutes turn it on again. If the display does not light up, and the OPERATE indicator remains flashing after the unit is turned on again, the unit may be in failure.
7Error messages
When multiple amplifiers are connected by F.C.B.S., the error messages described in the table below may be displayed on the display. In such a case, ID number setting or remote cable connection may be in failure. Check the ID number or remote cable connection, referring to the table below. For details on ID number setting, see “HOW TO SET ID NUMBERS”, on page 21.
| Indication | Meaning | Measures to be taken | |
1 | ERROR 02 | Multiple amplifiers |
|
|
|
| take ID No. 2. | A s s i g n d i f f e r e n t | |
2 |
| Multiple amplifiers | ||
ERROR 03 | ID numbers to the | |||
|
| take ID No. 3. | amplifiers. |
|
3 | ERROR 04 | Multiple amplifiers |
| |
|
| |||
|
| take ID No. 4. |
|
|
|
| The amplifiers with | If the amplifier with ID | |
|
| No. 1 is not on, turn | ||
|
| ID | it ON. |
|
4 | ERROR 11 | communicate with |
| |
|
| the amplifier with | Check that the remote | |
|
| c a bl e i s | p r o p e r l y | |
|
| ID No. 1. | connected. |
|
|
|
|
| |
|
| The amplifier with | If multiple | amplifiers |
|
| take ID No. 1, set ID | ||
|
| ID No. 1 cannot | numbers properly. | |
5 | ERROR 12 | communicate with | ||
|
| the amplifiers with | Check that the remote | |
|
| c a bl e i s | p r o p e r l y | |
|
| ID Nos. | connected. |
|
|
|
|
|
26