The test device or loop resistance measuring device is used for contact-free testing of the earthing resistance in electrical systems. The tester with self-luminous inverse LC display, simultaneously shows resistance (0.010 - 1200 ohms) and alternating current (0.00 mA - 20.0 A) and has a measurement data memory, adjustable alarm function when the limit is exceeded, an automatic switch-off and a data hold function. The robust device has a large measurement range with high resolution, an exact, reliable and stable power and a high noise immunity.The tester is microprocessor-controlled and allows accurate earth resistance measurement. The integrated filter technology effectively minimizes measuring interferences.The design of the product complies with protection class 2 and is double or reinforced insulated.This text is machine translated.