Fluke 5700A Series Service Manual page 307

3109 A15: HV +DC Preamplifier Fault
The instrument is set to the dc 1100V range with the amplitude set to 220V, 600V, and
1100V. The output of the DC HV AMPLIFIER/AC SENSE BUFFER circuit of the High
Voltage/High Current assembly is measured for 0.55V ±0.2V. This voltage is divided to
create HV MUX2 which is routed to Diagnostic circuit on the High Voltage Control
assembly where it is connected to the SDL line for measurement by the adc circuit on the
DAC assembly.
3110 A15: HV +DC Series Pass & Current Fault
The instrument is set to the dc 1100V range with the amplitude set to 220V, 600V, and
1100V. HV MUX3 from the HV DC OUTPUT SERIES PASS & CURRENT LIMIT
circuit on the High Voltage/High Current assembly is measured for -0.035V ±0.02V. HV
MUX3 is routed to Diagnostic circuit on the High Voltage Control assembly where it is
connected to the SDL line for measurement by the adc circuit on the DAC assembly.
3111 A15: HV +DC High Voltage Output Fault
The instrument is set to the dc 1100V range with the amplitude set to 220V, 600V, and
1100V. This output voltage is divided to create MUX5 which is connected to the SDL
line for measurement by the adc circuit on the DAC assembly. This failure occurs if the
expected output voltage is not within 12% of the nominal.
3112 A15: HV +DC Ref/error Amplitude Fault
The instrument is set to the dc 1100V range with the amplitude set to 220V, 600V, and
1100V. The control signal AMPLITUDE from the Magnitude Control circuitry of the
High Voltage Control assembly is measured. The nominal gain from AMPLITUDE to
HV OUT is 135. This gain is checked by measuring AMPLITUDE to be 0.0074 of the
nominal output ±25%. AMPLITUDE is divided to create MUX7 which is connected to
the SDL line for measurement by the adc circuit on the DAC assembly.
3113 A15: HV -DC Preamplifier Fault
The instrument is set to the dc 1100V range with the amplitude set to -220V, -600V, and
-1100V. The output of the DC HV AMPLIFIER/AC SENSE BUFFER circuit of the High
Voltage/High Current assembly is measured for 2.3V ±0.2V. This voltage is divided to
create HV MUX2 which is routed to Diagnostic circuit on the High Voltage Control
assembly where it is connected to the SDL line for measurement by the adc circuit on the
DAC assembly.
3114 A15: HV -DC Series Pass & Current Fault
The instrument is set to the dc 1100V range with the amplitude set to -220V, -600V, and
-1100V. HV MUX3 from the HV DC OUTPUT SERIES PASS & CURRENT LIMIT
circuit on the High Voltage/High Current assembly is measured for -0.035V ±0.02V. HV
MUX3 is routed to Diagnostic circuit on the High Voltage Control assembly where it is
connected to the SDL line for measurement by the adc circuit on the DAC assembly.
3115 A15: HV -DC High Voltage Output Fault
The instrument is set to the dc 1100V range with the amplitude set to -220V, -600V, and
-1100V. This output voltage is divided to create MUX5 which is connected to the SDL
Troubleshooting
Interpreting Diagnostic Fault Codes
5
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