Voltage Fluctuation

VOLTAGE,RY-415V,YB-400V,BR-420V&RN-220V,YN-208V,BN-222V

CURRENT,R-120A,Y-165A,B-115A

From these data, it seems u have given maximum load on Yellow phase.(May be some single phase load). As the load in one phase will increase, the voltege of that phase will decrease. So, try to distribute the load equally. Also, u should check the tightness of the cables.

Dear,

Fluctuation observed is due to Combination of Earth resistance = 4 Ohms ( High), & Un balanced load in your system. fact is confirmed by N - E volts = 2 Volts. Very healthy system , V n - e < 1 Volt.

I have solved this kind of problem at quite a few places.... ( Bank, IT centre, residential complex )

Remedies....

Have strong earth system near Neutral of Supply Transformer sub station < 0.5 Ohms practically. Although allowed is <5 Ohms. You may need to add 3 more electrodes in the neutral system.

Check Neutral conductor carrying the unbalanced current has sufficient capacity, if not, add neutral conductor from your mains up to the supply syetem's neutral.

Equalize the load current in your 3 phases.

Equalize the load currents in 3 phases of your Co consumers( If possible )

All the above remedies shall stablize the neutral to near 0 V & Vn-e wiil be <1 V at full load.

TRY & BE CONFIDENT.

Please turn off your capitals key. All capital letters are considered shouting and impolite in these types of forums.

Thanks.

Any voltage fluctuations willl be as a result of turning on and off loads hanging on the distribution network.

Please turn off Caps Lock.