Why grounding mat is important near ground switch operating handle and disconnecting switch operating handle?

Why grounding mat is important near ground switch operating handle and disconnecting switch operating handle?
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1 Answer

Answer :

Equipment operating handles deserve special attention because of the higher probability for co-incidence of adverse factors. For example,

a. Hand operation equipment such as grounding switches and disconnecting switches requires the presence of operator near a grounded structure at a point where opening of an energised circuit can some times result in an arc to the structure or perhaps mechanical failure and electrical break down of a switch insulator. A large percentage of fatal accidents from voltage gradients are in fact associated with operating handles. Hence in order to avoid above problems following should be an additional safety factors: 

1. Use closer mesh in the vicinity of operating handle area (150-mm approx.) and operating handle shall be directly connected to the earthing mat. 

2. Use higher resistance surfacing such as crushed rock or both in order to bring down the values of touch potential and step potential.  
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Last Answer : Both have same meaning. The term earthing is used in U.K. and grounding in U.S.A.ground means earth.

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How grounding resistance could be measured?

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What does mean by grounding electrode, grounding system, and grounding resistance?

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How system grounding and equipment grounding achieved?

Description : How system grounding and equipment grounding achieved?  

Last Answer : System grounding is obtained by grounding the neutral through resistance, through transformer and through effective or solidly grounding. Equipment grounding is obtained by Grounding of non-current carrying metallic parts ... cables. d. Body of portable equipment such as iron, oven, etc.   

Why grounding is necessary?

Description : Why grounding is necessary?

Last Answer : The purpose of grounding is to maintain the surface under and around a station ate as nearly zero potential as possible with reference to absolute earth so that operating staff who walk in the ... equipments are ate earth potential and when faults occur there is safety to staff and equipments. 

How safety could be ensured by equipment grounding?

Description : How safety could be ensured by equipment grounding?  

Last Answer : In order to enumerate this, let us first find out the effects of current and voltage developed during fault condition. 

What does mean by equipment grounding?

Description : What does mean by equipment grounding? 

Last Answer : Grounding of non-current carrying metallic parts is called equipment grounding. For instance no-current carrying parts include the following: a. Motor body, switchgear metal enclosure, transformer tank, conduits of ... . Sheath of cables. d. Body of portable equipment such as iron, oven, etc.