Transformer Calibration Instrument Calibration Device

The transformer testing instrument, from the perspective of its measurement principle, can be divided into two types: direct comparison and differential measurement.

Early transformer calibrators were primarily designed based on the direct comparison principle, which involves directly comparing the secondary voltage or current of a standard transformer with that of the transformer under test. This is achieved by feeding the secondary voltage or current of both transformers into the transformer calibrator, where they are measured using circuits such as resistance potential dividers, capacitance potential dividers, and magnetic potential comparators. The resulting difference in voltage or current is then processed to obtain the ratio difference and phase difference of the tested voltage or current transformer relative to the standard transformer.

The advantage of this transformer ratio tester is that the transformer ratio between the standard transformer and the transformer under test does not need to be equal. As long as the rated primary voltage or current of the standard transformer is greater than or equal to the rated value of the transformer under test, direct calibration can be performed, making it convenient to use.

This current transformer calibrator has the drawback that it cannot verify secondary loads less than1VA's current transformer; secondly, the inherent error of this transformer tester is directly added to the error of the standard transformer, as the component errors of the transformer tester limit the accuracy class of the tested transformer. For instance, a transformer tester's measurement error limit is ±0.05% due to its component limitations, even with a higher accuracy standard transformer, it can only be used to calibrate transformers below the 0.5 accuracy class. Therefore, this drawback restricts the application scope of the direct comparison transformer tester.

The transformer ratio meter based on the differential principle inputs the secondary voltage or current of the standard transformer and the tested transformer into the differential circuit of the transformer tester, then the differential stage sends it to the measurement stage for comparison with the secondary working voltage or current of the transformer, providing the ratio difference and phase difference of the tested transformer relative to the standard transformer.

Since this transformer calibrator is solely used to measure the difference between the standard transformer and the transformer under test, the error of the transformer calibrator is only the error of the difference between the two transformers, thus its impact on the measurement result is naturally much smaller. Generally speaking, regardless of the calibration level of the transformer being tested, as long as the standard transformer meets the specifications and the error limit of the transformer calibrator does not exceed±2% is sufficient. This not only makes the transformer calibrator easy to manufacture but also reduces costs, while significantly broadening its application range. The transformer calibrator is a differential type of calibrator.

The Transformer Calibration Instrument is a novel automated testing device that utilizes advanced electronic technology to directly decompose the error signals of transformers. After appropriate calculations, it simultaneously displays the transformer's percentage points, phase error, and orthogonal error in digital form. The instrument is easy to operate, with intuitive readings and rapid measurements, capable of reducing energy consumption and labor intensity. It is compact, lightweight, easy to carry, and suitable for on-site testing.The product was tested under a rated working current (voltage) of 5%; in addition, it is required that our company can also produce a current transformer calibration instrument with a secondary voltage of 100/3V, which can measure the error of current transformers at a rated working current of 1%; during the detection process, the instrument can easily perform self-calibration at any time to ensure accuracy; key components use imported parts, ensuring stable and reliable quality, widely used in metrology, power supply departments, and manufacturers of transformers, making it an ideal instrument for transformer testing.

Transformer Calibration Instrument, and Equipment for Accuracy Grade Verification0.01 to 10 levels, rated secondary currents of 5A and 1A current transformers, and rated secondary voltages of 100V, 100/V, 150V (100/3V, 220V) voltage transformers. Measurement results are displayed digitally, and can be equipped with an RSC232 interface for easy connection to a computer.

During the calibration of transformers, the instrument can measure the active and reactive components of the impedance or admittance of the secondary circuit of the transformer under test at any time.

During the calibration of transformers, the instrument automatically indicates polarity. In case of incorrect polarity, the instrument automatically breaks the differential current (differential pressure) circuit, ensuring the safety of the instrument's input circuit. It also emits an alarm to alert the calibration personnel.

The equipment can be used as an AC potential meter in a rectangular coordinate system, measuring small AC currents or voltages.

Equipment can be isolatedThe company measures the secondary voltage drop of voltage transformers, including PTs and operation boxes, together.

During the calibration of transformers, the instrument can be calibrated using a standard current transformer or a standard voltage transformer as the reference, or with a two-stage current transformer, two-stage voltage transformer, or an inductive voltage divider as the proportional standard.

Equipment can be subject to periodic verification using either the integral or component method.

Welcome to using our equipment. Although it is very user-friendly, please take the time to carefully read the user manual before operating the instrument.