Fluke 5720A 3422 A12 AC Cal Sensor 20V Range, Assembly A12 Missing, Assembly A13 Missing

5700A/5720A Series II Calibrator

Service Manual

measured via the RCL line. The output of this ac/ac sensor is measured by comparing it to the DAC assembly output voltage. The difference is measured to be 0V ±100 mV. A failure indicates the Oscillator Control assembly (A12) is probably at fault.

3422 A12: AC Cal Sensor (20V Range)

The instrument is set for 21.9V 1 kHz and configured as in the 20V range ac/ac calibration. The output of the ac/ac sensor on the Oscillator Control assembly is measured via the RCL line. The output of this ac/ac sensor is measured by comparing it to the DAC assembly output voltage. The difference is measured to be 0V ±100 mV. A failure indicates the Oscillator Control assembly (A12) is probably at fault.

3423 Assembly A12 Missing

At power up the instrument checks to see what assemblies are not installed. This test confirms that the Oscillator Control assembly is not responding. A failure indicates the Oscillator Control assembly (A12) is probably at fault.

3424 Assembly A13 Missing

At power up the instrument checks to see what assemblies are not installed. This test confirms that the Oscillator Output assembly is not responding. A failure indicates the Oscillator Output assembly (A13) is probably at fault.

3425 Assembly A12 Or A13 Not Responding

Communication with both Oscillator assemblies is checked. A failure indicates that one or both assemblies are not responding.

3426 A12: 8255 Was Reset

The control word of the 8255 on the Oscillator Control assembly is read. A failure indicates the Oscillator Control assembly (A12) is probably at fault.

3427 A13: 8255 Was Reset

The control word of the 8255 on the Oscillator Output assembly is read. A failure indicates the Oscillator Output assembly (A13) is probably at fault.

3500 A16: 8255 Control Word

The diagnostics software reads the control word of the 8255 IC on the Power Amp assembly. A failure indicates the Power Amp assembly (A16) is probably at fault.

3501 A16: 8255 Port A

The diagnostics software writes and reads data to port A of the 8255 IC on the Power Amp assembly. A failure indicates the Power Amp assembly (A16) is probably at fault.

3502 A16: 8255 Port B

The diagnostics software reads port B of the 8255 IC on the Power Amp assembly. A failure indicates the Power Amp assembly (A16) is probably at fault.

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