Metering current transformers and the protective current transformers differs in roles and design, but require the same common current transformer testing practices to ensure their electrical condition, and that they are properly connected to the rest of the system.
Though there are several procedures in current transformer testing, there are some common routines that should be part of testing practices, and those should cover transformer ratio, burden, polarity, phase deviation, excitation and insulation tests, among other specific testing.
The Vanguard EZCT-2000C Plus Automated CT Test Set a microprocessor-based current transformer test set designed specifically for Current Transformer (CT) testing.
The EZCT-2000C Plus’s test leads can be connected to all the CT output terminals, and the complete CT test can be performed automatically without any operator intervention.
Excitation Test
CT excitation testing is performed using the ANSI/IEEE C57.13.1 test method, with test voltage ranges from 50, 300, 500,1200 and 2000 Vac can be selected for the excitation test.
CT Winding Insulation Resistance Test
The EZCT-2000C Plus offers an IR test feature that can also measure the insulation resistance of the CT’s secondary winding using a test voltage up to 1000 Vdc.
Ratio and Polarity Tests
CT current-ratios are determined using the ANSI/IEEE C57.12.90 measurement method.
Demagnetization
The test set automatically demagnetizes the CT under test when performing an excitation test.
Winding Resistance Test
The test set can measure the DC resistance of transformer windings from 100 micro-ohms to 10 ohms.
CT Burden Test
The EZCT-2000C Plus can measure the CT’s actual connected burden by injecting a 1A or 5A test current into the load.
Related electrical test equipment available for rent from Protec:
Megger MRCT Relay and Current Transformer Test Set
Omicron CT Analyzer
Raytech CT-T1 Current Transformer (CT) Tester
This electrical test equipment is available for rent, lease, or purchase from Protec Equipment Resources. We are here to help you with your testing equipment needs.
Protec’s Calibration Lab offers accurate and affordable calibration services for all makes and models of electrical test and measurement equipment. Contact us today for a quote.
