 鲜花( 30)  鸡蛋( 0)
|
Earth Ground Testing. f0 N5 q/ `9 z7 S) N
( s7 u* P1 y' S8 _% g) P6 ?
Most 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., W% l( l# H( s2 z8 O O% L. S5 @
9 P# ^* b: Z5 @: S, e
Understand 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. |
|