Fluke 5720A 3321 A9/A10 10M Ohm Ratio Fault, 3322 A9/A10 19M Ohm Ratio, 3323 A9/A10 19M Ohm Ratio

5700A/5720A Series II Calibrator

Service Manual

3321 A9/A10: 10M Ohm Ratio Fault

The 2/5/10V SOURCE circuit on the Ohms Cal assembly is set to 10V which is routed to the Ohms Main assembly and connected to the 10 MΩ string. The resulting 1V across the 1 MΩ portion is measured for 1V ±3% ±15 mV. A failure indicated the Ohms Main assembly (A10) is probably at fault.

3322 A9/A10: 19M Ohm Ratio 1

The 2/5/10V SOURCE circuit on the Ohms Cal assembly is set to 10V which is routed to the Ohms Main assembly and connected to the 19 MΩ string. The resulting 1V across the 1.9 MΩ portion is measured for 1V ±3% ±15 mV. A failure indicated the Ohms Main assembly (A10) is probably at fault.

3323 A9/A10: 19M Ohm Ratio 2

The 2/5/10V SOURCE circuit on the Ohms Cal assembly is set to 10V which is routed to the Ohms Main assembly and connected to the 19 MΩ string. This 10V across the 19 MΩ portion is measured for 10V ±3% ±15 mV. A failure indicated the Ohms Main assembly (A10) is probably at fault.

3324 A9/A10: 100M Ohm Ratio Fault

The 2/5/10V SOURCE circuit on the Ohms Cal assembly is set to 10V which is routed to the Ohms Main assembly and connected to the 10 MΩ string. The resulting 1V across the 1 MΩ portion is measured for 1V ±3% ±15 mV. A failure indicated the Ohms Main assembly (A10) is probably at fault.

3325 A9/A10: 10 Kilohm Check Fault

The Current assembly (A7) outputs 0.13 mA which is routed to the Ohms Main assembly (A10), via INT OUT HI, where it is connected to the 10 kΩ string. The voltage drop across the 10 kΩ string is measured for 1.3V ±3% ±15 mV. Measure this voltage drop by connecting the DMM hi to TP5 and the low to TP6 of the Ohms Cal assembly (A9). If the voltage is out of tolerance, the Ohms Main assembly is probably at fault. If the voltage is within tolerance, the Ohms Cal assembly is probably at fault.

3326 A9/A10: 19 Kilohm Check Fault

The Current assembly (A7) outputs 0.13 mA which is routed to the Ohms Main assembly (A10), via INT OUT HI, where it is connected to the 19 kΩ string. The voltage drop across the 19 kΩ string is measured for 2.47V ±3% ±15 mV. A failure indicates the Ohms Main assembly is probably at fault.

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