 鲜花( 30)  鸡蛋( 0)
|
Earth Ground Testing4 {& w. h& q5 V3 i; Z) C7 M7 R% z. E
! t2 i6 y" c" a4 `
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.7 D) [4 L W+ v* g+ S5 d, W8 ~8 H
0 `1 R" l, ~7 z% M) w. i# CUnderstand 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. |
|