Troubleshooting Down Programmer
The down programmer discharges the output when either PWM OFF is generated or CV ERROR is more negative than about - 3Vdc. Comparator A5U1 triggers down programming when the voltage at
Circuit Included. Down programmer and 10.6V bias supply on A1 main board.
Setup. The Main Troubleshooting Setup, Page 53, except connect the external supply to the unit's + OUT ( + ) and - OUT (
-) terminals. Apply the ac mains voltage to the isolation transformer. Set the external supply for an output voltage of 10Vdc and set current limit for 2.5 Amps. Set the power supply under test for a voltage setting of 8.0Vdc and current setting of 2.0Adc using the ''DISPLAY SETTING" switch.
Outputs: |
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NODE ( + ) * | EXTERNAL SUPPLY | MEASUREMENT |
A5C1 ( + ) C3(6031A) | ON/OFF | 10Vdc |
A5VR1(K) | ON/OFF | 6.5Vdc |
ON/OFF | 0.2Vdc | |
A5CR1( K ) CR2(6031A) | OFF | 0.6Vdc |
A5CR1( K ) CR2(6031A) | ON | 0.2Vdc |
OFF | 0.5Vdc | |
ON | 5.0Vdc | |
A5R20 + (6030A/35) | OFF | < 0.001Vdc |
A5R20 + (6030A/35) | ON | 1.5Vdc |
across A5R1(6031A) | OFF | < 0.001Vdc |
across A5R1(6031A) | ON | 0.10Vdc |
across A5R14(6032A) | OFF | < 0.001Vdc |
across A5R14(6032A) | ON | 0.17Vdc |
* NODE |
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Troubleshooting CV Circuit
Circuits Included. Constant Voltage (CV) Circuit and buffer amplifier A2U5B.
Setup. The Main Troubleshooting Setup, Page 53. Apply the ac mains voltage to the isolation bias transformer, and disconnect the external supply. Remove the + S jumper and connect
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