As per section 194A of the Act, the core banking solutions of the banks and societies have to be taken into account for considering whether the TDS has to be applied or not.
Form15G/Form15H is only a declaration that no TDS should be deducted on your interest income since tax on your total income is nil. Interest income from fixed deposits, recurring deposits, and corporate bonds is always taxable.
TDS is to be deducted at the rate of 10%. If the recipient of income doesn’t furnish his PAN to deductor, then TDS is to be deducted @ 20%. No surcharge, education cess or SHEC will be added to the basic rates.
Section 194A deals with a deduction of TDS on interest other than ‘interest on securities’. This could include Fixed Deposits & Loans and Advances other than banks. This TDS is deducted for resident individuals only.