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LINUS14/14D
4. OPERATION
4.3 Mains protection
4.3.1 Inrush current limitation
Within one second of the LINUS14/14D amplifiers being connected to the mains, the inrush current limiter will charge the
primary capacitors in a controlled way, limiting the maximum mains current during startup.
4.3.2 Mains overvoltage detection
There is a overvoltage protection in the mains input. If the mains input voltage exceeds 270 V, the main power supply
remains switched off and a high, loud buzzing tone sounds from the device as a warning.
4.4 Main SMPS protection
4.4.1 Overcurrent protection
The main SMPS (Switched Mode Power Supply) transformer current of your LINUS14/14D amplifier is continuously
monitored. If overcurrent occurs, the main SMPS immediately stops 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 reduce 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 (no clipping or only slight clipping) this protection should never be activated.
4.4.3 Thermal protection
The temperature of the main SMPS transformer of your LINUS14/14D amplifier is permanently monitored. If the temperature
exceeds 70° C/158° F, a thermo limiter will act on the total system power and avoid a SMPS shutdown.
4.5 Fans
The fans mounted in your LINUS14/14D amplifier operate permanently, but as long as the temperature remains below
40°C /104°F, they will run at their slowest speed. The highest detected temperature from the heatsinks of each channel and
SMPS transfortmer controls the speed of the fans. Above 40°C/104°F the speed is increased until it reaches its maximum
value.