MC4 is no stranger to photovoltaic practitioners, it has almost become synonymous with photovoltaic connectors. MC4 can be found in the important components of photovoltaic power generation, such as modules, junction boxes and inverters, and they are responsible for the successful connection of power plants.

MC4 is no stranger to photovoltaic practitioners, it has almost become synonymous with photovoltaic connectors. MC4 can be found in the important components of photovoltaic power generation, such as modules, junction boxes and inverters, and they are responsible for the successful connection of power plants.

As of the end of 2015, China's cumulative installed capacity of photovoltaics was 43.18GW, ranking first in the world. Based on 1MW usage of approximately 4,200 sets of photovoltaic connectors, there are currently approximately 180 million connectors installed in China. Viewed from a risk perspective, it means that at least 180 million risk points need to be monitored by different power plant owners.

Despite this, this small component is often overlooked during the design, construction and operation of the power station. The reason is very much related to everyone's understanding of MC4.

Maybe it's time to get to know MC4 again!

1. A small history of photovoltaic connectors

For photovoltaic connectors, 1996 and 2002 are two very important years. These two points in time also coincide with the key development nodes of the photovoltaic industry. Although the photovoltaic connector has not come along with the photovoltaic industry, its appearance has greatly promoted the rapid rise of photovoltaic installations.

Before 1996, photovoltaic cables were connected using screw terminals or splice connections. With the increase in the installation of photovoltaic systems, the industry's demand for fast, safe and easy-to-operate connection solutions is becoming stronger.

Because the photovoltaic system is exposed to wind, rain, hot sun and extreme temperature changes for a long time, the connector must be able to adapt to these harsh environments. They must not only be waterproof, high temperature resistant and weather resistant to ultraviolet rays, but also have touch protection, high current carrying capacity and high efficiency. At the same time, low contact resistance is also an important consideration. All of this must also run through the entire photovoltaic system life cycle, at least 20 years.

In 1996, based on these application environments and market demands, a new type of plug-in connector came into being. This is the world's first truly photovoltaic connector MC3. Its inventor is the Swiss company Multi-Contact (in 2002, merged into the Stäubli Group as its electrical connector brand), MC is the brand abbreviation, and 3 is the size of the metal core diameter. The main body of MC3 uses TPE material (thermoplastic elastomer), and cooperates by friction to achieve physical connection. More importantly for MC3, its connection system uses MULTILAM technology to ensure the long-term stability of the connection. Later, many connector manufacturers are imitating MULTILAM technology.

In 2002, the birth of MC4 redefine the photovoltaic connector again, it truly realized "plug and play" (plug and play). The insulating material uses hard plastic (PC / PA), and it is easier to assemble and install on site in design. After the MC4 was launched, it was quickly recognized by the market and gradually became the standard for photovoltaic connectors. Many manufacturers call their connectors "× MC4". If you search for MC4 on Alibaba, you can get about 44,000 related products, which shows the strong market influence of MC4.

With the change of market demand, MC4 has successively launched MC4-Evo2 and MC4-Evo3 series. MC4 series connectors have been able to fully meet customer needs for 1500V photovoltaic systems.