24/7 Wall St.

There are several stocks trading more heavily than usual this morning, and also experiencing large gains or drops in share prices. These include Plexus Corp. (NASDAQ: PLXS), NetScout Systems Inc. (NASDAQ: NTCT), Hanwha SolarOne Co. Ltd. (NASDAQ: HSOL), F5 Networks Inc. (NASDAQ: FFIV), and Johnson Controls Inc. (NYSE: JCI)

After the first hour of trading, Plexus is up more than 13% at $37.64. Volume has already topped the daily average of 312,000 shares traded. The contract electronics manufacturer beat earnings estimates and has forecast higher revenues for the current quarter.

NetScout is up nearly 12% at $19.03. Volume is already higher than the daily average of 280,000 shares traded. The services delivery management company delivered better-than-expected revenues and earnings but lowered its EPS and revenue estimates for the full fiscal year.

Hanwha SolarOne is up nearly 9% at $2.04. Volume is near the average daily volume of 1.02 million shares traded. The solar panel maker is rising on expectations that prices have stabilized and that shipments will rise.

F5 Networks is up more than 11% at $120.89. Volume is already more than double the daily average of about 1.9 million shares traded. The network software maker reported better-than-expected quarterly revenues and earnings.

Johnson Controls is down more than -8% at $32.62. Volume is already nearly double the daily average of 4.7 million shares traded. The auto parts and control systems supplier posted solid earnings, but lowered forecasts.

Paul Ausick