Ilt-2 Temperature Related Power Supply Failure - Agilent Technologies PSG Series Service Manual

Troubleshooting
Getting Started with Troubleshooting

ILT-2 Temperature Related Power Supply Failure

Thermal Shutdown
When a thermal shutdown condition occurs, the front panel green LED and the power supply LEDs will blink
until the condition is eliminated. Two thermistors in the signal generator monitor temperature. One is
located in the A19 Power Supply and the other is located on the A8 Output. If the thermistor temperature is
exceeded, a signal is sent to the A3 Power Switch that shuts down the signal generator. The A19 Power
Supply thermistor will shutdown when its temperature exceeds 105 degrees centigrade. The A8 Output
thermistor shuts down when its temperature reaches approximately 92 degrees centigrade.
To troubleshoot, do the following:
1. If the fan is working, allow the signal generator to cool down.
2. If the signal generator is still shutting down, remove A8 Output to eliminate one thermistor.
3. If the signal generator is still shutting down, replace the A19 Power Supply.
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