Camco Amplifier - Manual (Page 24)

4 OPER
ATION
USER MANUAL
VORTEX 3 QUADRO P.22
impedance limiter is active, the corresponding channel’s On LED is turned off.
(See 6 Troubleshooting)
4.3.3 SOA Protection
Whenever the power transistors leave their Safe Operation Area (SOA), the SOA-
protection in stereo mode switches back the current rail of the respective power
stage. In mono modes the rails of both channels of one amplifier are switched
back.
4.3.4 Speaker Protect Limiter
Whenever the SOA protection of the power amp switches back the current rail
there could be a small clipping at the output; but the microprocessor is also
triggered by this protection and will reduce the signal level immediately to
minimise the effect.
The user can decide either to use Speaker Protect or not. If you use this amp for
low frequencies (bass / Sub bass) and you want to squeeze the absolute maxi-
mum out of it, Speaker Protect can be switched off. For all other applications
(e.g. Full Range) it’s recommended to keep Speaker Protect switched on.
4.3.5 DC Protection
Each output of the power amp is constantly monitored for persistent DC voltage
levels. If the 3 V thresholds are exceeded at any of the outputs, main SMPS will
shut down and the channel at that output will be automatically disconnected.
The microprocessor performs a sophisticated strategy to locate the cause of DC.
If short-term DC is detected, the amplifier will recover and continue to operate.
DC can be located in the output stage, driver stage or at the input of the amplifier.
Output Stage
When a DC voltage is located at an output stage, the main SMPS remains
switched off. The On LEDs will show a flash sequence corresponding to this
malfunction. (See 6 Troubleshooting)
Driver Stage
When a DC voltage is located at the driver stage only the defective channel’s
output stage and the DCA are muted. The other channel continues to work.
The On LED of the defective channel will indicate the malfunction by starting
the relevant flash sequence. (See 6 Troubleshooting)
Amplifier Input
When DC is located at the input stage only the DCA of the affected channel is
muted. (The other channels continue to operate normally). If the DC signal at
the input vanishes the microprocessor will de-mute the affected channel and
the amplifier will work as usual again.
4.3.6 DC Servo
To prevent DC Offset at the speaker output the VORTEX is fitted with two DC
Servos per channel. (Hence there are no capacitors in the signal path!)
4.3.7 Over Current Protection
Over current is permanently controlled in the output stage. There are two limi-
ting levels of over current depending on output voltage. These limits will be set
automatically. This improves reliability without degrading sound quality when
driving complex loads.
4.3.8 Thermal Protection
The microprocessor uses several sensors in the amp in order to ascertain tem-
perature data. If the microprocessor detects a temperature of more than 85 °C
at the heat sinks, the input signal on that channel is reduced. If the temperature
exceeds 00 °C, the main SMPS is switched off.
The On LED of the overheated channel will start a blinking-sequence.
(See 6 Troubleshooting)