Precision AC Current Measurement—Built for Utility Testing The TESCO Metering AC Current Probe (Catalog No. 411) is a high-accuracy Hall Effect measurement tool designed for meter shop, substation, and field environments. Ideal for applications that require safe, isolated AC current measurement, this probe expands the capabilities of the TESCO Metering CT Ratio/Burden Tester (Catalog No. 1047). Available as a standalone probe or with ISO 17025 calibration certification.