CoinDCX automatically gives you the additional margin and charges interest @0.05% per day (or 0.05/24 % per hour). Additional margin is the amount a trader has borrowed from the exchange to fulfill a particular order. When the position is open for more than 24 hours, the interest expense is calculated for an order based on the following formula:
Interest Charged = (Interest rate Per Hour * hours *additional margin) / 100
where Additional margin = (Order Value - Locked Balance for the order).
The count of hours starts after first 24 hours.