Indicators; Cleaning - Ecler GPA2-400 Bedienungsanleitung

4.3. Indicators

GPA amplifiers include a simple yet effective indication system.
CLIP indicators (1, 5) show the absence of loudspeaker output signal. These indicators may light
up for following reasons:
1. During start-up, until the STANDBY time has passed. This time period is needed for the
internal operating voltages to settle.
2. A short circuit is detected at the loudspeaker terminals (PROTECT function).
3. The amplifier is outputting direct current or very low frequency signals that could damage the
loudspeaker.
In any case, should these indicators light permanently, this is a sign of malfunction and the
causes should be investigated.
The clip indicators light up just before the actual clipping threshold at the loudspeaker output is
reached. The clip detection circuit considers supply voltage oscillations, so that a dependable clip
reading is achieved, even when operating with unstable mains voltage. It is usual that the CLIP
indicators shine following the bass frequencies when the amplifier operates at high power levels, as
these frequencies carry the main energy. Take care that the CLIP indicators are not permanently lit.
SP Signal Presence indicators (2, 4) indicate the presence of a valid signal at the amplifier inputs.
The TH (THERMAL) (7) indicator* lights when the unit has entered the protection mode due to
excessive temperature; normal operation is recovered when the amplifier internal temperature comes back
down to regular operating levels.
*
ONLY GPA2-400

5. CLEANING

The front panel should not be cleaned with dissolvent or abrasive substances because silk-
printing could be damaged. To clean it, use a soft cloth slightly wet with water and neutral liquid soap;
dry it with a clean cloth. Be careful that water never gets into the amplifier through the holes of the front
panel.
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