An impedance analyzer is an electronic test instrument that measures the characteristic complex impedance curves of a ...

Making a device to test an RCD is easy; a resistor between hot and the protective ground circuit would do. [Callan] over-engineers. He used a 50 W resistor where 30 W would do under the worst ...

In other words, with the perfect setup, you could put a digital panel meter that reads the voltage in the circuit, and read the resistance directly ... the device under test and two more wires ...