Transformer Neutral Earth Pit Problem.

If everything has "...got too much heated..." then it's time to find out why so much current is flowing. You may have a severely unbalanced system, a low-level earth fault somewhere, and/or are in need of additional earthing pits and a way to keep them wet enough to keep on "earthing" for you.

Your post is confusing. I will make the assumption that you have a wye connected secondary with the neutral point connected to your earth pit. The voltage between phases RB, RY or YB should be 415 volts. The voltage from R,B or Y to neutral/earth should be 230 volts. Neutral to E should be zero. In your post you say"B-E = 0 volts." The only way that could happen is if you had a delta connected secondary with B grounded. Your statement R-Y-E = 415 volts can not be right. What do you mean by "touching the neutral to another earth pit" ? You can have a difference in potential between earth pits. You may have sparking occur in this situation. Please add some additional information.

Given the figures you state you've lost the neutral star point earth connection and now have a phase to earth fault. Is the neutral solidly bonded or via a NER? Failure of the NER followed by a phase to neutral will give the figures you quote.

As for getting sparks when you connected the two pits, I surprised you didn't get a big bang!

I think the same as TonyS in the "first pit"case the neutral was not grounded but phase B was.

In the second case "pit no.2" a short-circuit occurred between phase B and the neutral through the Ground , the connection to ground of phase B burnt out and delivered phase B from its earth connection.

Typical "Indian" way of problem solving?

Absolutely not

"so that we take a cable & touches the neutral to another earth pit then a spark will come & after that everything is ok".

Then what? Rather than analysing the problem, you brag that you touch the neutral to another earth pit & gosh! spark will come????

Had it been a site with inflammable or explosive materials, what your 'spark' could have created?

A well deserved Darwin Award....

As we think neutral is disconnected from its pit so we just connect one pit with another and a very little spark came just like we discharge a fan capacitor.

both Earth pit & its surroundings got too much heated

Do you mean that the ambient temperature got really high, the ground dried up and the earth pit resistance increased?

The solution is to isolate the installation from all sources of power on the basis of danger to life and property, and to hire a qualified HV Electrician to put things right. Wasting time on CR4 only increases the chances of hurting/killing someone. So do it now/this morning/immediately.