Industry jargon

Current transformer

Also called: CT, CT clamp A current transformer, or CT, measures alternating current by producing a smaller proportional signal that monitoring or control equipment can read. It allows a load-management system to measure high site currents without routing the full load through the controller itself. In an EV charging installation, CTs are commonly fitted around incoming conductors or selected feeders so the control system can see how much current the site is drawing. That measurement can then be used to increase or reduce charging power. CT direction, ratio and location matter. If a CT is fitted to the wrong conductor, installed backwards or configured with the wrong ratio, the control system can make decisions using incorrect site-load data.