A dedicated probe box creates a low-resistance high-current path and plug-in detection, helping multimeters measure up to 30 A without heat damage.
A detachable meter pen box lowers loop resistance with copper inserts and elastic terminals, enabling safer 30A multimeter testing.
A parallel current-diverting coil with an air-gapped magnetic core redirects DC leakage from AC lines to prevent transformer saturation and overload.
A shunt-based measuring circuit detects overloads and opens the semiconductor switch before damage, while enabling threshold-based restart control.