Equipment Required for Verifying Instrument Transformers

Basic equipment required for current transformers includes:



1. Transformer calibrator: Measures the error between the standard transformer and the transformer under test, and displays the working current.



2. Standard current transformer: Used as a standard in transformer verification, with accuracy generally two or more levels higher than the tested transformer, designed with multiple ratio taps to accommodate verification of different transformers.



3. Current generator: Works in conjunction with a voltage regulator to produce various required test currents. Its capacity and cost increase with the current.



4. Load box: Simulates the actual working condition of the transformer under test.



5. Voltage regulator: Used to adjust the test current, generally installed in an operating console with protection and switches, including coarse and fine adjustment regulators to meet adjustment precision. For measurements below 2500A rated current, a combination of 10KVA general-purpose voltage regulators can be used; for larger currents, special fabrication is required, typically 30~60KVA.



6. High-current connecting cables: Connect currents of hundreds or thousands of amperes; the cost of cables cannot be ignored.



Basic equipment required for verifying voltage transformers includes:



1. Transformer calibrator: Measures the error between the standard transformer and the transformer under test, and displays the working current.



2. Standard voltage transformer: Used as a standard in transformer verification, with accuracy generally two or more levels higher than the tested transformer, designed with multiple ratio taps to accommodate verification of different transformers.



3. Voltage generator: Works in conjunction with a voltage regulator to produce various required test voltages; its capacity and cost increase with the voltage.



4. Load box: Simulates the actual working condition of the transformer under test.



5. Voltage regulator: Used to adjust the test voltage, generally installed in an operating console with protection and switches, including coarse and fine adjustment regulators to meet adjustment precision. Generally, a combination of 10KVA general-purpose voltage regulators is sufficient.