Automated HV Capacitance Bridge
From Measurements International

Model 7010B	Applications Shunt Reactor Loss Measurements Power Transformer Measurements Calibration of Potential Transformers Calibration of Low Voltage Std. Capacitors Calibration of High Voltage Dividers Calibration of High Voltage Power Capacitors Inductance Measurements Measurement of Low Loss, High Voltage Power Loss Tangent Measurements to 10% Corona Loss Measurements Insulator and Dielectric Testing

The model 7010B is a capacitance bridge with a ratio of 1000:1 making it ideal for both low and high voltage applications. The automatic self-balancing feature facilitates the use of the bridge for accurate load loss measurements of large high voltage inductive loads

• Automatic Self Balancing
• Current Comparator Technology
• 3-4 Terminal Measurements
• Lead Compensation Circuit
• Overall Accuracy 15 ppm
• Range Extension Option with 7020H

The 7010B may also be used for calibration of precision standard capacitors, tan-delta measurements and of precision potential transformers. Overall accuracy is <15 ppm in magnitude and phase. The technology is based on the two-stage-current-comparator principle. The 7010B has a capacitance ratio up to 1000:1 and dissipation (loss tangent) of 0 to 10% with a resolution of 1 ppm. To accommodate capacitance ratios larger than 1000:1 an additional two stage range extender, model 7020H, may be added to increase the ratio to 2,000,000:1. All connections are made on the rear of the instrument. The model 7010B is fully protected against transients.
The effect of lead and winding impedance on the measurement accuracy has been reduced by means of a built-in lead compensation circuit

Compensated Current Transformer Model 7020

Single Range Highest Permeability Wide Measurement Range Negligible Current Errors Low Burden Low Uncertainties

The Model 7020 series of Compensated Current Transformers use passive, two stage compensated technology. The main advantage of a two stage compensated CT is that the effective burden is low when feeding into another compensated CT such as the current input on the Model 2010A Wattmeter or Cx & Cxp input to MI 7010 Capacitance Bridge. As result, the errors of the CT are effectively reduced to zero in both magnitude and phase. Lead length becomes unimportant and there is no further concern for any additional active components.

The Model 7020 was originally developed as an extender for the MIL Model 2010 Wattmeter where the accuracy over the full range is important. It is also suitable to be used as a standard current transformer for CT Test Sets or for measuring range extension for Tan Delta measurements of high capacitance & low inductance values using the Model 7010 series of Capacitance Bridge. The Model 7020 has 50% over-range capability. Compensated Current Transformer.

The model 7020 is supplied as single 2000:1 ratio device. The housing consists of a Formica enclosure for the strength and protection required in industrial environments.