Current Transformers, Transducers & Transmitters

Current transformers (CTs) are used when the current in a circuit is too high for direct measurement by instruments or electronic equipment. They “step down” high currents—often thousands of amperes - to standardized, measurable levels such as 5A or 1A. This ensures that sensitive measuring instruments remain protected while providing accurate readings. There are two primary types of CTs: Measuring current transformers, which work with instruments to monitor current magnitude, power, and energy usage. Protective current transformers, which pair with protective relays or trip coils in breakers to detect faults and initiate circuit protection.

Current transducers serve as the interface between the power system and the measurement or control system. They convert non-standard electrical currents into usable, standardized outputs - such as transforming an AC input signal into a DC output signal. Through magnetic induction, they isolate and scale current flow, safeguarding connected monitoring and control devices from excessive currents. Current transmitters, often integrated with CTs or transducers, further condition the output signal for transmission to monitoring or automation systems. They provide reliable, linear, and proportional signals for use in SCADA systems, meters, and controllers. Together, these devices ensure accurate energy management and circuit protection across a wide variety of applications.