Voltcraft vc 539 digital clamp multimeter voltcraft vc 539 use this voltcraft vc 539 current clamp meter to measure electrical values up to cat iii 600 v in compliance with en 61010 1 please see the technical specification for the measurement functions ranges current is measured using a magnetic current clamp sensor all other measurements are conducted using the included safety test leads the product has a backlit lcd display with 4000 counts automatic range selection and a hold function