This is about the recent problem that we have faced in our project site. We have 6/7.5 MVA. 66/11kV three phase star - star power transformer. The neutral was solidly connected to the earthing mat. But because of high resistance of earthing mat (130 ohm on LV and 180 ohm on HV), one day LV side neutral earthing conductor melted and we had a huge damage. Can any one plz tell me what might happen when we connect power transformer neutral to the earthing mat which has high resistance (>100 ohm ) ?????
2 2689why we are connecting the alternator to a steam turbine of higher RPM then the rated RPM of alternator? For example:( connecting 1500 rpm alternator to 7600 rpm steam turbine). we can directly connect the same rpm turbine to alternator know??? is there any special reason ???
2 2955why the vfd motor take current high in vfd panel then mcc panel.current in vfd panel=160A in 93%.and mcc panel it shows 130A. (132kw motor)
1 2089Post New Electrical Engineering Questions
Minimum IR value of 1.1 kv grade 3.5c (300, 240,185,150,120,95,70,50,35,25) sqmm Aluminium XLPE cable and 4c (16, 10,6 & 4) sqmm cu arm cable between RY,YB,BR,RN,YN,BN,RE,YE,BE & NE.
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