PAT testers for patients-discharge-current according to PAT 0751. You have to do different measurements on electric meters of the protection classes I, II and III for the protection of users if you do changes or new installations. With this PAT tester the measurements according to DIN PAT 0701/ 0702/ 0751 and VBG4 can be carried and the control of protective conductor resistance, surrogate-arrester-, current-current, insulation resistance, voltage-freedom and earth leakage current is given. Gauges- and patient-discharge-currents can be measured in residual-current-procedure or as surrogate-arrester-current. Take care to the implementation: In the surrogate-patients-discharge-current every application partial has to be measured particularly. The RS-232 interface and the software enable the documentation of the measurements and there evaluation