supply , erection , testing and commissioning of 48 volt battery charger for charging 500ah 48v battery set for switchyard of 2x500 mw , btps , anpara . , supply of 48 volt battery charger for charging 500ah 48v battery set having technical specification ( of existing cell ) as follows: ( i ) ac input: 415v + 10% , 3 phase , 50hz ( ii ) dc output: ( a ) capable of float charging a battery of 24 lead acid cells at 2 . 15v per cell while supplying a continuous load of 50a ( b ) capable of boost charging a battery of 24 lead acid cells at a maximum charging current of 30a and up to 2 . 65 v per cell . , erection , testing and commissioning of above battery charger and replacement of old battery charger and its storage at a suitable specified place .