Tneb — CC charges without proper reason

Address:

Chennai, Tamil Nadu

The Electricity bill for the months of April and May 2015 is originally Rs.820/-. As per the unit count given in the calculator on the TNEB website, I have used 320 units which amounts upto Rs. 820. An additional charge of Rs. 500 was added as 48100-Cc Deposit. I stay as a tenant and I do not think that this is a fair charge. Can someone please help?