AVTECH ELECTROSYSTEMS AVR-GHV1-B, Instructions Manual

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PREVENTING OUTPUT STAGE FAILURE
The output stage is protected against overload conditions by an overload circuit and
fuses on the main frame back panel. However, the output switching elements may fail if
the unit is triggered at a PRF exceeding 1 kHz or if the load impedance is too low (<
100 kΩ or > 330 pF). Heating and subsequent possible failure of the output stage is
reduced if the following action is taken where possible:

PRF is kept to a minimum, i.e. operate in a low PRF range when possible rather
than in a high PRF range.

Keep the output PW to a minimum.

Never apply an externally generated voltage to the output port.

Reduce the amplitude below 100 Volts before changing the output polarity. Note
that internal protection circuits will prevent the polarity from switching when the
amplitude is set higher than ±100V, until the internal power supplies have
discharged the voltage on the internal energy-storage capacitors to below ±100V.
This may take several seconds.

Use the correct load impedance (> 100 kΩ and < 330 pF).

Keep output cable lengths to 2 meters (6 feet) or less.
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