Before 1996, there were no special optoelectronic connectors on the market. The photoelectric cable is connected through a universal screw connector or a joint connection, and the insulating tape is connected to the outside. This method is time consuming, laborious and unreliable. As the number of installed photovoltaic systems increases, everyone wants a fast, safe and easy-to-operate connection scheme.

      Therefore, based on these application environments and market demands, a new type of plug-in connector was born in 1996. This is the real photoelectric connector-MC3. Its inventor is the Swiss Multi-Contact company (founded in the Stäubli Group in 2002), MC is the abbreviation of the brand, and 3 is the size of the metal core diameter.

      In 2002, the introduction of MC4 redefines the optoelectronic connector again, truly realizing "plug and play". Hard plastic (PC/PA) is used as the insulating material, which is easier to assemble and install on site in the design. After the MC4 was put on the market, it quickly gained market recognition and gradually became the standard for optoelectronic connectors.

      Since Multi-Contact is the first professional manufacturer of optoelectronic connectors in the world, many standards have been formulated, which has had a great impact. Many people mistakenly believe that the foreign name of optoelectronic connectors is MC4, but in fact it is not in this way. With the circulation of products, MC4 has gradually become the so-called abbreviation, synonymous!