 鲜花( 30)  鸡蛋( 0)
|
Earth Ground Testing' k/ _1 w/ ]& c4 F2 D% X
, w6 p" u8 x- w% n. q
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.
H$ M2 ]0 I$ z2 ?0 F/ b; w2 e
- e+ p1 z2 J) IUnderstand 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. |
|