Protection Circuits - Beko HLV-2000 Instruction & Operation Manual

The HLV-2000 operation is internally monitored by many highly efficient protection circuits.
If any limit is exceeded the device shuts off. If any protection circuit is activated the red
"PROTECTION"-LED illuminates as well as one of the three protection circuit LEDs
"ANTENNA", "OVERDRIVE" or "TEMPERATURE". At the same time, an acoustic
signal sounds. The internal beeper can be switched off when not needed. Access to the micro
th
switch is through the 17 air gap in base plate in the near of the Standby switch. An alarm
signal of 5V DC is fed to Pin 1 of the "CONTROL"-jack for any monitoring purpose. To
turn the amplifier on again the "RESET"-switch must be turned off for a short time and then
on again.
Attention:
Please insure that the amplifier is disconnected from the mains when disabling
the audible alarm.

7. Protection circuits

The HLV-2000's internal control circuit supervises the output load condition, any overdrive
of the input stage and the thermal status of heat sink and power supply unit. If the amount of
reflected power exceeds 100 watts, the protection circuit shuts off the RF unit immediately
and switches the drive power to bypass mode. This also happens with overdrive levels of
more than 15% of the rated value or when overheating the amplifier by >55°C or 130°F.
CAUTION
This amplifier uses a new and ultra fast overdrive detection for cutting off all kinds of
alc overshoot and spikes >3 db of rated input level coming from the transceivers used .
Input levels up to 150 watts are kept away from the expensive rf transistor's input.
Although the internal protection circuits are very efficient they cannot assure a 100%
safety. Direct radiation due to too small a distance between the antenna and the
amplifier can cause feedback effects or falseing of the threshold levels of the protection
circuits.
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