levels occur Then, as temperatures in the amplifier heat sinks increase, the automatic thermal-sensing circuitry will cause high-speed operation to occur. Depending upon signal conditions and amp loading, high-speed fan operation may continue or the fan may cycle continuously between high and low. This situation is quite normal. If cooling is inadequate, however, the amplifier thermal-sensing system may cause temporary shut down of the unit, indicated by the LEDs on both channels going dark. Inadequate cooling may be due to preheated air, reduces air flow resulting from blockage of inlet/outlet ports, severe amplifier overload, or short circuit conditions. Depending upon the available cooling air, operation should be restored relatively quickly, and the power LED on both channels will again be illuminated. In any event, action should be taken to correct the cause of the thermal shutdown. If the amplifier is not severely overloaded or shorted and air flow is normal in and out of the amplifier, then steps should be taken to provide a cooler environment for all the amplifiers. As a general rule, the cooler electronic equipment is operated, the longer its useful service life.
In most low to
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