Description:
The 1620-A is a self-contained assembly of the 1615-A Capacitance Bridge with appropriate oscillator and null detector for measurements at 11 frequencies between 50 Hz and 10 kHz. For applications requiring other or higher frequencies, to 100 kHz, the 1615-A Bridge can be supplied separately and the oscillator and detector selected to meet your needs.
The 1615-A Capacitance Bridge brings to the measurement of capacitance, the intercomparison of standard, and to the measurement of dielectric properties an unusual degree of accuracy, precision, range, and convenience.
High accuracy is achieved through the use of precisely wound transformer ratio arms and highly stable standards fabricated from Invar and hermetically sealed in dry nitrogen. For calibration these standards can be intercompared.
Two- or Three- Terminal Connection - Accurate threeterminal measurements can be made even in the presence of capacitances to ground as large as 1 μF, as might be encountered with the unknown connected by means of long cables. The bridge has the necessary internal shielding to permit one terminal of the unknown capacitor to be directly grounded, so that true two-terminal and three-terminal measurements can both be made over the whole capacitance range.
Convenient Operation - For both capacitance and dissipation factor, the balance controls are smoothly operating, lever-type switches, The readout is digital and decimal point is automatically positioned. Each capacitance decade has a - 1 position to facilitate rapid balancing.
The 1615-A elementary diagram is also clearly delineated on the front panel of the bridge. Changes in connections and grounds are automatically indicated, as you switch the bridge terminals for diff erent measurement conditions.
Extend Range to 11.1 F - With the 1615-P1 RangeExtension Capacitor, the 1615-A will measure to a maximum of 11.11110 F. This capacitor plugs into front-panel bridge terminals and can be adjusted for calibration to the bridge standards.
Features:
Accurate and precision measurements of capacitance and dissipation factor
Measurement of circuit capacitances
Dielectric measurements
Intercomparison of capacitance standards diff ering in magnitude by as much as 1000:1
10-5 pF to 11.1 μF, 2- or 3- terminal
0.01% accuracy, 1 ppm resolution
Lever balance, in-line readout
Reads dissipation factor or conductance
Capacitance Measurement:
Range: 10 aF to 1.11110 μF (10-17 to 10-6 F) in 6 ranges, direct reading, 6-figure resolution; least count 10-17 F (10 aF). With Range Extension Capacitor, upper limit is 11.11110 μF.
Accuracy: At 1 kHz, ±(0.01% + 0.00003 pF). At higher frequencies and with high capacitance, additional error
is: [±3 x 10-5% + 2 (CμF) x 10-3% ±3 x 10-7 pF} x (fkHz)2 At lower frequencies and with low capacitance,
accuracy may be limited by bridge sensitivity. Comparison accuracy, external standard to unknown,1 ppm.
Dissipation Factor:
Range: At 1 kHz, 0.000001 to 1; 4-figure resolution, least significant digit count: 0.000 001 (10-6);
range varies directly with frequency.
Accuracy: ±[0.1% of measured value + 10-5 (1 + fkHz + 5fkHzCμF)].
Conductance:
Range: 10-6 μS to 100 μS, ranges +, 2 ranges-, 4 figure resolution, least count 10-6 μS, independent of frequency, range
varies with C range.
Accuracy: ±[1% measured value + 10-5 μS + 6 x 102fkHzCμF x (1 + fkHz + 5fkHzCμF)μS].
Frequency:
Approximately 50 Hz to 10 kHz. Useful with reduced accuracy to 100 kHz. Below 100 Hz, resolution better than 0.01% or 0.01 pF required preamplifi er or special detector.
Standards:
1000, 100, 10, 1, 0.1, 0.01, 0.001 and 0.0001 pF. Temperature coefficient of capacitance is less than 5 ppm/C for the 1000, 100, and 10 pF standards, slightly greater for the smaller units.
Generator:
Maximum safe generator voltage (30 x fkHz) volts, 300 V max. If generator and detector connections are interchanged, 150 to 500 V can be applied, depending on switch settings.
IET 1311-A Audio Oscillator is recommended.
