Fluke 5720A 3116 A15 HV -DC Reference/error Amp Fault, 3119 A14/A15 HV +DC Current Abs. Value

5700A/5720A Series II Calibrator

Service Manual

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.

3116 A15: HV -DC Reference/error Amp 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.

3117 A14/A15: HV +DC Current Error Amp Fault

The Calibrator is set to the dc +2.2A current range with the amplitude set to +0.22A, +0.6A, and +1.2A. The control signal AMPLITUDE from the magnitude control circuitry of the High Voltage Control assembly is measured to be within 25% of the expected value. AMPLITUDE is divided to create MUX7 which is connected to the SDL line for measurement by the adc circuit on the DAC assembly.

3118 A14/A15: HV -DC Current Error Amp Fault

The Calibrator is set to the dc -2.2A current range with the amplitude set to -1.2A. The control signal AMPLITUDE from the magnitude control circuitry of the High Voltage Control assembly is measured to be within 25% of the expected value. AMPLITUDE is divided to create MUX7 which is connected to the SDL line for measurement by the adc circuit on the DAC assembly.

3119 A14/A15: HV +DC Current Abs. Value

The instrument is configured to the +DC 2.2A range and set for an output of 0.22A, 0.60A, and 1.2A. The output current from the High Voltage/High Current assembly is routed to the Current assembly where it is connected to the 1.2Ω load resistor. The Current control signal G OUT from the High Voltage/High Current assembly is routed to the Absolute Value Circuit on the High Voltage Control. The output from the Absolute Value circuit should be = 2.17 * I, ±25%, where "I" is the output current. This voltage is divided creating MUX6 which is connected to the SDL line where it is measured by the adc circuit on the DAC assembly.

3120 A14/A15: HV -DC Current Abs. Value

The instrument is configured to the -DC 2.2A range and set for an output of -1.2A. The output current from the High Voltage/High Current assembly is routed to the Current assembly where it is connected to the 1.2Ω load resistor. The Current control signal G OUT from the High Voltage/High Current assembly is routed to the Absolute Value Circuit on the High Voltage Control. The output from the Absolute Value circuit is a positive voltage which should be = 2.17 * I, ±25%, where "I" is the output current. This voltage is divided creating MUX6 which is connected to the SDL line where it is measured by the adc circuit on the DAC assembly.

3121 Spare

This fault code is not used.

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