ITEC | Instrument Transformer Equipment high voltage transformer, Current Transformers. Voltage Transformers, Combination Metering Unit, Station Voltage Transformers, Dry Type Transformers Instrument Transformer Equipment Corporation manufactures instrument transformer products, and offers a broad variety of product designs well suited for voltage transformer and current transformer service applications. Our products include the CTO Line of Current Transformers, VTO Line of Voltage Transformers, CVTO Line of Combination Metering Unit, PST Line of Station Service Transformers, and the DCR Line of Dry Type Transformers.