what is the resistance value of earthing pit and why they
are connected?

Answer Posted / ajoy kumar

In some cases like rocky soil, the resistance value of individual earthpit become more than 5 ohms. For these cases, we can consider the combined earthing and it should be atleast less than 1 ohm.

Is This Answer Correct ?    2 Yes 2 No



Post New Answer       View All Answers


Please Help Members By Posting Answers For Below Questions

can we start slipring motor on star delta like we start induction motor ? if yes where will we connect ?

1500


WHERE CAN I GET THE PREVIOUS QUESTION PAPERS OF Govt Polytechnic in deee 2nd year papers

2306


how to revers the direction of single phase motor

480


How will A Medium voltage circuit breaker(11 kV voltage level) operate under short circuit fault condition whether It is having short circuit release like Low voltage circuit breaker or relay should be given?

1433


if any body have question paper of railway (section engineering),then plz send me .i will thank of him/her.

1581






What is thresh hold value of current?

1604


What are root loci?

657


What are the major reasons for balancing hydro-thermal mix?

688


Rules and standards of electrical control wiring ?

644


what is the use of piston rings in the engine used for a generator...........

1699


what are the parameters plays a major role in Potential transformer Burden calculation??

1615


what is mean by ideal infinite bus? why it is required to consider in fault short circuit calculations?

2243


How do i right a ladder diagram that has 1 actuator that performs a full stroke followed by a half stroke

1628


If i am running of spindle at 2000rpm ,but How to spindle stop at the second I am resetting the machine in CNC machines

1232


When we use air circuit breaker, it has O/L protection ,time delay SC protection, Instataneous SC protection & ground fault protection. They all have some setting range. But what is the suitable/allowable setting for the above protection which will be safe for the equipment? For example-O/L protection setting have a range of (0.4,0.45,0.5,0.55,0.6,0.65,0.7,0.8,0.9,1.0)xIn Time delay SC protection have a range of (1.25,1.5,2,3,4,6,8,10,12)xIn Time delay setting is 0.02,0.1,0.2,0.3,0.4 Instataneous setting is fixed to 20xIn Gound fault setting is given 100A,300A,600A,900A,1200A This setting are for 2500A ACB. So what will be the basic allowable setting for the above protection? is there any formulae to calculate this<

1682