Sharp JX-8200 Service Manual page 66

SHARP SERVICE MANUAL JX8200SM [8] ADJUSTMENTS
(3) 24V power overcurrnet protection detection level adjustment
1) Turn RV701 fully counterclockwise.
2) Connect 4A load (1.25Ω, 30W or more) to the 5V power.
Insert a resistor of 1.25Ω (30W or more) across the resistor R777.
3) Connect 7.25A load (3.3 Ω, 200W or more) to the 24V power.
(Insert a resistor of 3.3 Ω (200W or more) between the output pin FT701 and GND.)
4) Turn on the power.
5) Set the voltmeter to the 24V power output.
Set the volmeter between the output pin FT701 and GND.
6) Slowly turn RV701 clockwise and stop it when the 24V power is turned off.
(4) POFF signal output detection level adjustment
1) Connect 0.1A load (50 Ω, 2W) to the 5V power.
Connect a resistor of 50 Ω (2W) across resistor R777 (between 5V and GND).
Set the 24V power to non-load state.
2) Set the voltmeter or oscilloscope between the POFF signal (Connector CN703 7pin) and GND.
3) Set the AC power input voltage to 61V (100V series) 122V (200V series) with the AC power voltage adjuster (slidac transformer).
4) Turn RV702 to set the POFF signal to 5V.
5) Slowly turn RV702 until the POFF signal output becomes 0V.
FT701
GND
R777
GND
R777
RV701
CN703(7pin)
RV702
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