Equity Linked Saving Scheme (ELSS) are exempt from tax u/s 80C. The total exemption limit u/s 80C is INR 1.5 Lakh.
Section 80C includes various investments. Therefore your investment in ELSS during the financial year contributes to this total limit of INR 1.5 Lakh u/s 80C.
The earnings more than INR 1 Lakh from ELSS in a financial year are taken as capital gains and taxed accordingly.