The 820 is a Hand Held Capacitance Meter from BK Precision. Capacitance meters are used to measure discrete capacitors and come in bench and portable varieties.
- Manual Ranging Capacitance Meter
- Range: 10 ranges with full scale values from 999.9 pF to 999.9 mF. Reads from 0.1 pF to 999.9 mF
- Accuracy: 0.5% of full scale ± 1 LSD (least significant digit) on 1000 pF to 100 µF ranges. 1% of full scale ± LSD on 1000 µF to 1000 mF ranges
- Resolution: 0.1 pF on 1000 pF range; .01% of full scale on all ranges
- Reading Time: 0.6 SEC max to 1000 µF, increasing to 35 SEC at 1 Farad
- Overrange: All ranges, bottom segment of all digits light up giving (- - - -) indication
- Display: 4-digit LED Display
- Front Panel Controls: 10-position range switch, zero adjust, on-off switch
- Test Connections: Spring-tensioned slot type capacitor socket and banana jacks for accepting standard test leads
- Power Source: 4 standard "C" Cells (4.4 to 6 volts). Nicad, alkaline, or zinc carbon, with provision for charger
- Battery Life: At least 6 hours continuous operation. At least 2 weeks of typical intermittent use
- Operating Temperature: 0 to 50° C (32 to 100° F)
The BK Precision 820 Capacitance Meter operates as a time counter to measure the charge time required for the measured capacitor to reach a specific voltage. Circuit design is based upon the RC time constant property. The meter uses a precision constant current source to charge the capacitor and a precision voltage reference to which the capacitor is charged. Charging time then becomes solely dependent upon the value of the capacitor being measured. Each range selects a different combination of precision charging current, clock frequency, and charge voltage reference which permits direct capacitance readings in pF, nF, µF, or mF.