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LINUS10
4. OPERATION
4.3.4 Overcurrent protection
The output stage is permanently monitored for possible current surges. There are two limiting levels of overcurrent
depending on output voltage. These limits will be set automatically. This improves reliability without de grading sound
quality when driving complex loads.
4.4 Mains protections
4.4.1 Inrush current limitation
Within 2 seconds of the LINUS10 amplifiers being connected to the mains, the inrush current limiter will charge the
primary capacitances in a con trolled way, limiting the maximum mains current during startup.
4.4.2 Mains overvoltage detection
The mains overvoltage detection is always operative. When the mains volt - age exceeds approx. 267 V (230 V operation),
or 134 V (120 V operation) the amplifier will switch off. When the mains voltage returns to nominal value, a soft start occurs.
4.4.3 Mains surge overvoltage protection
The LINUS10 is fitted with a varistor unit, protecting the SMPS from spo radic surge overvoltages coming from the mains
distribution. If active, this protection is indicated by a orange LED behind the dust cover (on the right side}. If this LED is
not lit, this means that the amplifier has already suffered significant overvoltages surges and that the varistor protection
needs to be exchanged.
4.4.4 Mains failure detection
Mains Failure Detection is always operative. When the mains supply is interrupted for approx. more than 4 mains cycles,
the amplifier will detect and display a mains voltage loss. When the mains voltage returns to a normal value, a soft start
occurs and the amplifier returns to normal/previous operation.
4.4.5 Fuse protection
When driving the LINUS10 at very high output levels over a longer period of time (i.e. several seconds and minutes) the
average mains current draw can become very high. In such situations, the FuseProtect limiter will re duce the output signal
in order to prevent the external mains breaker from tripping. But this limiter in turn will not affect the output signal on
dynamic music signal and short current peaks, thus guaranteeing the full available peak output power.
Due to the very large output power of the LINUS10, this limiter has been set to a maximum average mains input current
of approx. 24 A.
This design choice has been made to achieve the best compromise be tween mains breaker tripping protection and long
term output power ca pabilities of the LINUS10. This choice allows the LINUS10 to deliver more output power over a longer
time period, which it is easily capapable of. But in turn this also means that mains breaker tripping still can occur when
driving the LINUS10 at very high output levels over a longer time period.
Please note that the FuseProtect limiter only controls the average mains input current, not the short term peak input
current. This means that with very dynamic music signals the (short term) input current can still reach very high levels,
which can be very demanding for a mains distribution. See also chapter 3.3.3. If active, by a red LED behind the dust cover
(approx. in the top middle of the dust cover).