ABB announced today that it will acquire Thomas & Betts, doubling ABB’s addressable low-voltage products market in North America to about $24 billion. Both companies’ boards of directors have agreed to a transaction in which ABB will pay about $3.9 billion.

The complementary combination of Thomas & Betts’ electrical components and ABB’s low-voltage protection, control and measurement products will create a broader low-voltage portfolio that can be distributed through Thomas & Betts’ network of more than 6,000 distributor locations and wholesalers in North America, and through ABB’s distribution channels in Europe and Asia.

“Strategically, it’s a great fit,” said Joe Hogan, ABB’s CEO. “This is another big step toward our goal of expanding our presence in the key North American market.”

The transaction will also enable Thomas & Betts to accelerate its global growth strategy, noted Dominic J. Pileggi, Thomas & Betts’ chairman and CEO. “This is the right time for this transaction, and I believe strongly that ABB is the right partner for our business going forward.”

Thomas & Betts, combined with ABB’s North American low-voltage products business, will become a new global business unit led out of Memphis, Tenn., under Pileggi’s leadership.

With estimated 2011 revenues of $2.3 billion, Thomas & Betts employs about 9,400 people. Its main business is the manufacture of low-voltage and ultralow-voltage electrical products such as connectors, conduits and fittings, as well as wiring management products for the construction, industrial and utilities markets. These are complementary to ABB’s offerings, which include products such as breakers and switches.

“This is a unique opportunity for ABB to grow in the largely untapped North American low-voltage products market,” said Tarak Mehta, executive committee member responsible for ABB’s Low Voltage Products division, into which Thomas & Betts will be integrated as a standalone unit. “We plan to keep and build on Thomas & Betts’ strong brand and product names. We have complementary products that can be sold together already today and other products that will take some time to introduce to customers.”

The transaction is structured as a merger, and is subject to approval by Thomas & Betts shareholders, as well as to customary regulatory approvals in both North America and Europe. It is expected to close by the middle of this year.