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PROTECTION
1. SWITCH ON MUTE PROTECTION -
The mute circuit is used at the inputs when the unit switched ON, output of between a few seconds the amplifier will
be muted. This is done so that turn-on/off noises from mixers and other gear is blocked in case the entire system is powered up at once.
2. SHORT CIRCUIT PROTECTION -
The PA series comes with built-in Output Short Circuit Protects. The Output Short
Circuit Protection protects the output devices of the amplifier from short circuits and stressful loads. If your speaker lines
shorted, the amplifier automatically detects this problem and discontinued operation for that channel. If one side of your
amplifier becomes shorted and goes into protect mode, the other side will continue to operate normally. Channel output during
the “Short Circuit Protection" will be interrupted (i.e. no sound output). Short Circuit Protection can usually be traced back to the
signal output line (i.e. speaker line). Check the line from the output terminal of the amplifier to the speaker. If this line is good,
check the internal speaker connections and components. A short circuit will usually be traced to a bad cable or a bad speaker
component and is rarely traced to the amplifier itself.
UNiKA
PA-664/PA-1804
3. OVERHEATING PROTECTION -
The PA series amplifiers are cooled by two variable speed fans, and always are kept at moderate temperature. During
low level output the fans run at normal speeds. During high output and as heat raises, (exceeding 50°C.), the fans will run at higher speeds to aid the cooling
process. If the heatsink temperature exceeds 91°C., the amplifier will mute until the amplifier cools down. When the amplifier cools below 90°C., the amplifier will
return to normal operations. Be sure not to operate your amplifier below the minimum load ratings to reduce the risk of overheating problems.
4. DC CIRCUIT PROTECTION -
If dangerous subsonic frequencies or direct current (DC) is detected in the amplifier's output, the unit will activate its DC/low-
frequency protection circuitry and the amplifier will be muted. This protects the loads and prevents oscillations. The unit will resume normal operation while the
amplifier no longer detects dangerous low-frequency or DC output.
Important Precautions Introduction
Front Panel Rear Panel Set Up Operating Modes
Specifications
Protection
