 鲜花( 30)  鸡蛋( 0)
|
Earth Ground Testing& U. i6 t* a& t4 h* X# Y! C
0 T' P6 @( A* J( N, m4 B+ LMost facilities have grounded electrical systems, so that in the event of a lightning strike or utility over voltage, current will find a safe path to earth. A ground electrode provides the contact between the electrical system and the earth. To ensure a reliable connection to earth, electrical codes, engineering standards, and local standards often specify a minimum impedance for the ground electrode. The International Electrical Testing Association specifies ground electrode testing every three years for a system in good condition with average up-time requirements." d; r: L0 k& i' y% R& ~3 x* |% T3 N
5 q; G% L* G( N/ x- _6 n$ tUnderstand earth/ground principles and safety in more depth and then describes the principle testing methods: 3 and 4 pole Fall-of-Potential testing, selective testing, stakeless testing and 2 pole testing. |
|