 鲜花( 30)  鸡蛋( 0)
|
Earth Ground Testing
2 v# N+ T3 [; U2 t8 x: v. H- _
- ] r; w/ e0 R# 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.; R$ C) P# t% W) z9 h
( X0 e+ c( u2 j2 Y: V" D
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. |
|