Offer for Wonderware

British engineering and electronics firm Siebe PLC began its $24-a-share tender offer Monday for Irvine-based software maker Wonderware Corp.

The offer, set to expire at 9 p.m., requires that a majority of the outstanding shares of Wonderware stock be tendered. Wonderware’s board unanimously approved the offer, which was announced last week.

Wonderware would become a wholly owned division of Siebe.