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POWER FAILURE DETECTOR
This unit is equipped with a power failure detector function included in the CPU which checks for an abnormal condition in the chassis power supplies, including the power supply derived from the horizontal output transformer.
If, while the power is on, a failure is caused by any of the following that results in a low voltage supply, the CPU will turn the unit off in 1.5 seconds to prevent unnecessary damage.
- Failure within the power supply circuits.
- A short circuit in the load side from the power supply
- Stoppage of the horizontal output oscillator caused by the X-Radiation protection hold-down circuit
If while the power is off, the power is switched on and any of these failures remains uncorrected, the CPU will shut off the power within 3 seconds. Check the following of the unit is turned off by power failure indicator.
- Disconnect the AC power cord [120VAC line] for at least 10 seconds.
- Connect a DC voltmeter to the following Test Points.
- Press the power key and check for the proper voltage supplies.
- If any of these voltages is low, the power failure detector should turn the unit off within 3 seconds.
- Check all the circuits listed above.