Use this method when the auxiliary earth spike cannot be stuck. In this method, an existing earth electrode with a low earth resistance, such as a metal water pipe, a common earth of commercial power supply and an earth terminal of a building, can be used with two-terminal method (E,P).
Use the simplified measurement probe attached which has a convenient structure that both the safety alligator clip and test bar are available
1 Wiring
Make connection as shown in the figure.
Note : When the simplified measurement probe are not used, short P and C terminals.