Neutral To Ground Voltage

Try to give more information about the generator

i think you have not done neutral earthing to generator

it is not a big problem. this problem may presist because of type of load connected. if you are having load like printers, fax machines, xerox machines etc

does the generator given output voltage same between line to line ?, coukd cause by unbalanced voltage. And please measure grounding resistance and suggestion : you could add grounding point

Sounds like you have a floating neutral in your generator system, ground your neutral and it should take care of the problem

The problem is that a high impedence voltmeter is being used to measure a floating neutral.

Earthing the neutral at the generator is part of the solution.

Switching to a moving coil voltmeter is the rest of it.

Never expect neutral to be at the same potential as earth anywhere on the distribution system afterwards; the difference reflects the voltage generated as a result of the neutral current flowing through the resistance of the neutral conductor.

BTW: the difference between earth and ground is the Atlantic Ocean.

Moving Coil Voltmeter reads only dc; it does not work on ac

Someone had better tell AVO about that!

Moving coil AC meters are rectified!

Ensure proper neutral grounding and the problem should be solved.

-Dhanshyam

Harmonics could be the cause of these PQ problems .Mention the type of load and CMD ???? Please do study with Power Quality Analyzer like KRYKARD-India etc ...and analyze the data . you can understand and totally clear the problem . Thanks B.Nagarajan

Is this a single or three phase generator?

As you are using neutral what is the voltage between neutral and phse at the same load as you are seeing your "problem" between neutral and earth?

Where exactly are you measuring?

What type of voltmeter are you using?

What load in amps have you got when seeing your "problem"?

Basically it seems the problem of improper neutral grounding. Because , when neutral is not grounded, you will see voltage between neutral & earth. In this case , you should isolate neutral from generator & measure the earth resistance of neutral earth. If neutral earth resistance found ok,then it might be connection problem at the generator end. Other wise reactivating of earthing required.

Its possible what you say, but if its a 3 phase generator and one or two phases are heavily loaded and the third phase only lightly loaded AND quite a long cable is in use, it is possible that the ground neutral voltage may rise.....

The ground and neutral should ONLY be bonded at the Generator by the way.....on a single or a three phase generator.

Its usually a good idea to have a thicker cable for the neutral as with single phase systems on a three phase output, all the loads go via the neutral. if the loads are balanced well, its not a problem...but if not.....

Neutal earthing continuty should be verified.Earth pit resistence should be verified.

verify the unbalance loads and correct the loads into balanced load.Then your problem will be solved.