Camarillo-based power supply maker Power-One slashed 300 more jobs July 24 as its losses steepened sharply in the second quarter.

The net loss felt by common shareholders spiked to $6.8 million from a loss of $3.9 million in the second quarter last year, the company said in an earnings announcement. Net sales also tumbled 39 percent from the previous year, to $149.3 million.

Power-One said the main driver for the losses was $3.9 million it paid out in severance costs after it announced plans to shutter its Dominican Republic factory earlier this year. The company said that move is expected to save it $15 million a year and followed the announcement of 1,000 job cuts earlier this year.

But 300 more job cuts proved necessary, bringing the company’s year-to-date reduction to 1,300 workers, nearly 30 percent of the company’s workforce.

In recent years, Power-One bought a promising company in Europe that makes power converters for solar and wind energy installations. But that has not been enough to combat a precipitous drop in global manufacturing demand.

Power-One’s shares have hovered in the $1.30 range most of this year, after failing to recover to the $3.75 they traded at in early 2008.

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