With the widespread application of photovoltaic power generation, the connection between photovoltaic modules and module strings, and the DC connection of junction boxes, inverters and other equipment have widely adopted international standard MC4 connectors.
So what are the performance requirements of photovoltaic connectors?
First, photovoltaic connectors must have good conductivity and the contact resistance must not be greater than 0.35 milliohms.
Second, they need to have sufficient safety performance to ensure the safety performance of solar cell modules. The environment and climate in which solar equipment is used may sometimes be in very bad weather and environment, so it must have waterproof, high temperature, corrosion resistance, high insulation and other properties, and the protection level should reach IP68.
Third, the structure of solar connectors must be firm and reliable, and the connection force of the male and female connectors that are correctly plugged in should not be less than 80N. For MC4 connectors connected to 4mm² cables, the temperature must not exceed the upper limit temperature of 105 degrees when carrying 39A current. MC4 connectors are single-core connectors with male and female heads, which have many advantages such as good sealing, convenient plugging, and convenient inspection and maintenance.
When purchasing MC4 connector plugs, pay attention to product quality, including the size compliance of the internal metal conductor, the material thickness, elasticity and coating should all meet the ability to carry large currents and good contact, and the plastic of the plug shell should ensure a smooth surface without cracks and good interface sealing. When installing the component connector, avoid exposure to sunlight and rain to avoid aging of the connector, rusting of the internal connector and cable, increased contact resistance, and even sparks, resulting in reduced system efficiency or fire accidents.
When installing the photovoltaic MC4 connector, the crimping link is the top priority, and professional crimping tools should be used. Before the construction of the photovoltaic power station, the relevant engineering installation personnel should be trained in crimping operations.
