 鲜花( 30)  鸡蛋( 0)
|
Earth Ground Testing
+ r. J# f- O k: \, x7 q p2 K
9 S/ G2 b: S2 Z# Z& V4 x6 OMost 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.
* F/ W; ]; r. p# _) ~! J5 e4 |& T
1 p" z! k7 z1 k" O+ EUnderstand 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. |
|