Sensex plunges over 500 points on global selloff; Nifty tests 17,600 : Rashtra News Equity benchmark Sensex slumped over 500 points in early trade on Wednesday, tracking losses in index majors HDFC Bank, ICICI Bank and Infosys amid heavy selloff in global markets. The 30-share Sensex was trading 501.74 points or 0.84 per cent lower