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LINUS10-C
4. OPERATION
4.2 Power amp protection systems
4.2.1 DC protection
Each output of the power amp is constantly monitored for persistent DC voltage levels. If the 15 V threshold voltage is
exceeded at any of the out puts, the SMPS will be automatically switched off to prevent further damage from overload to
the power amplifier and speakers. In this case the display will show "DC Error", so that only a complete disconnection of the
mains power brings the amplifier to a restart. A DC issue can be located in the output stage, the driver stage, or at the input
of the amplifier.
4.2.2 Output stage
When a persistent DC voltage is located at an output stage, the main SMPS will be permanently switched off. This will be
indicated on the display as "DC Error".
4.2.3 Overload protection
The output stage is permanently monitored for possible overload situations. There are varying limiting levels of overload
protextion depending on input mains voltage. These limits will be set automatically. This improves reliability without de-
grading sound quality when driving complex loads.
4.3 Mains protection
4.3.1 Inrush current limitation
Within 1 second of the LINUS10-C amplifiers being connected to the mains, the inrush current limiter will charge the
primary capacitors in a con trolled way, limiting the maximum mains current during power-up.
4.3.2 Mains overvoltage detection
There is NO overvoltage protection! The customer needs to be sure to only use the LINUS10-C in the voltage range printed
on the label on the back of the unit!
4.4 Main SMPS protection
4.4.1 Overcurrent protection
The main SMPS (Switched Mode Power Supply) transformer current of your LINUS10-C amplifier is continuously monitored.
If overcurrent occurs, the main SMPS immediately will stop working. Should there be an internal failure, this feature
prevents other parts from being damaged.
4.4.2 Overload protection
In case of extremely high output levels with heavily clipped output signals and low loudspeaker impedances < 2.5 Ω, this
additional protection will re duce the amplifier stage output power very quickly. If activated, this indicates that the amplifier
is running close to its absolute maximum power capacity and the limit LEDs on the front panel are flashing.
In normal operation this protection should never be activated.
4.4.3 Thermal protection
The temperature of the main SMPS transformer of the LINUS10-C ampli fier is permanently monitored. If the temperature
exceeds 75° C/167 °F, the main SMPS will switch off. The amplifier’s display will indicate a "Power error" in this case.
4.5 Fans
The fans mounted in your LINUS10-C amplifier operate permanently, but as long as the temperature remains below 40° C/
104° F, they run at their slowest speed. The highest detected temperature from the heatsinks channel controls the speed of
the fans. Above 40° C/104° F the speed is increased until it reaches its maximum value.