At the interbank foreign exchange, the rupee opened at 71.83 then fell to 71.89 against the US dollar.
After opening slightly higher, the 30-share index turned negative to trade 41.31 points, or 0.10 per cent, lower at 40,610.33.
After scaling a lifetime (intra-day) high of 40,816.38, the 30-share index ended 181.94 points, or 0.45 per cent, higher at 40,651.64.
After hitting a high of 40,816.38, the 30-share index was trading 321.20 points, or 0.79 per cent, higher at 40,790.90.
Positive opening in domestic equities and easing crude oil prices supported the domestic unit.
After hitting a high of 40,736.14 in early trade, the 30-share index pared some gains to quote 177.67 points.
The 30-share index ended 185.51 points, or 0.46 per cent, higher at 40,469.70.
Trading in emerging market currencies were subdued tracking cautious opening in domestic equities.
The 30-share index pared some gains to trade 58.59 points, or 0.15 per cent, higher at 40,342.78.
The broader NSE Nifty slipped 10.95 points, or 0.09 per cent, to end at 11,884.50.