AR 2000W1000D, Operating And Service Manual

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Model 2000W1000D
38 Rev B
4.3.2 Power Supply Faults
The 500 Watt Power Amplifiers and Driver Control Unit have self-contained power supplies. In the event of
a power supply failure, the front panel display will identify which units power supply is at fault.
4.3.3 Thermal Faults
RF module thermal faults are detected. See section 4.3.5. The heatsink temperature is monitored and will
trigger a thermal fault if it overheats.
4.3.4 ALC Fault
Indication – ALC
As stated previously, the power limit controls could not limit either the forward or reverse power to the preset
threshold. This can be a transient type of problem, if the fault can be cleared. If the fault cannot be cleared
with no RF input drive power, then there is a malfunction in the ALC board or associated circuit.
4.3.5 RF Module Faults
Any RF module fault will trigger amplifier shut down, including main power supplies. There are three
possible module faults – Amplifier and Thermal. Module faults are displayed as AMP? or THERM? , where
? indicates the defective module within the 500 watt amplifier or driver amplifier.
Thermal faults usually indicate ambient temperature is too high, there is inadequate air-flow through the
module heat sinks or there is a problem with the sensor in the module.
Amplifier faults usually indicate there is a short circuit that would not clear on the module printed wiring
board or component, or the module current limit is not adjusted correctly or one of the output devices is
defective and/or not drawing enough current.