Since its introduction to the world nearly a century ago, the SQUARE D brand name has become synonymous with unsurpassed innovation, safety, and quality in the electrical industry. Today, as one of the three global master brands of Schneider Electric—along with TELEMECANIQUE and MERLIN GERIN—that reputation lives on.

The origin of the SQUARE D name is legendary. In 1915, the Detroit Fuse and Manufacturing Company introduced a stamped steel version of its enclosed safety switch. Embossed on the switch cover was a square with a capital 'D' for Detroit. The safety switch became so popular that customers requested the 'Square D' safety switch. Two years later, the company, capitalizing on the market demand for this product, changed its name to Square D Company. Today, the SQUARE D brand name remains one of the few created by its customers. in 1991, Schneider Electric acquired Square D Company and added one of the most highly recognized and well-respected brands in the electrical industry to its portfolio.

A respected international brand for more than 80 years, TELEMECANIQUE continues its rich heritage as a global leader in machine process and motor control applications. Since inventing the first industrial contactor in 1924, Telemecanique has continued to pioneer new electrical control technology including the development of the first thermal relays, float switches, and pressure gauges in 1925.

Innovative excellence continued to define the brand as new products were introduced over the next half-century in the areas of digital and speed control, photoelectric sensing, and human machine interface (HMI). Schneider Electric acquired Telemecanique in 1988. Today, TELEMECANIQUE remains the company's leadership brand for IEC type industrial control and automation products.




In 1920, Paul-Louis Merlin and Gaston Gerin created the Merlin Gerin Company and, in 1921, introduced the world's first range of high voltage, oil circuit breakers. Over the next 70 years, the strength of the MERLIN GERIN brand grew as the company expanded its operations worldwide.

Key MERLIN GERIN innovations include the pneumatically operated circuit breaker, the first 245,000 volt Hexabloc metal clad substation, the MULTI-9™ range of low voltage circuit breakers, the MASTERPACT® molded case circuit breaker, and the COMPACT™ NS circuit breaker. in 1992, Schneider Electric completed the acquisition of Merlin Gerin. Today, MERLIN GERIN remains a leading international brand in IEC type electrical circuit protection products.