Connector fittings in a solar system may seem insignificant, but they can have a significant impact on the safety and power generation efficiency of the entire system. Improperly selected connectors may cause poor contact, heat and fire or even system collapse. Currently on the market mainstream MC4 connector on dozens of brands, quality varies, the price ranges from a few dollars to hundreds of dollars, how to pick the right connector accessories become every solar practitioners need to master the skills.
The first connector to pay attention to is the certification standards. High-quality solar connectors should be through the TUV, UL and other international certifications, in particular, IP68 protection level and more than 1000V voltage resistance. Products of formal manufacturers will clearly identify these certification information, while poor-quality connectors generally lack the relevant certification, or the use of is forged certificates to carry out. Actual test results show that the uncertified connectors in a humid environment will rapidly degrade the insulation performance, the use of 1-2 years will be able to appear obvious aging.
Material selection is also very important. Good connector shell must use high-quality engineering plastics, with UV resistance, high temperature performance, the internal metal terminals are best silver-plated copper materials to ensure good conductivity and corrosion resistance. Some low-priced connectors on the market with poor-quality plastics and ordinary copper, in the outdoor environment will soon appear embrittlement, oxidation problems. There have been power stations due to the use of poor-quality connectors lead to increased contact resistance, the local temperature rises to more than 100 ℃, and ultimately lead to fire accidents.
Compatibility is another focus that requires special attention. Different brands of MC4 connectors seem to be compatible, but in fact there are tolerance differences. Mixing different brands of connectors may lead to poor contact, especially in places with large temperature differences, where thermal expansion and contraction can exacerbate the problem. It is recommended to use the same brand of connector throughout the system, if you must mix, at least to ensure that the plugging and unplugging force is moderate, tight contact.
The installation method also affects the service life of the connector. Professional installation requires the use of special crimping tools to ensure that the wire and the terminal close together. Many field workers in order to facilitate the use of ordinary pliers crimping, this practice is very likely to lead to poor contact. Crimping is also done after the completion of insulation protection to avoid moisture penetration. According to statistics, more than 90% of connector failures stem from faulty installation operations.
Maintenance should not be ignored. Even high-quality connectors need to be tested regularly. It is recommended to check the status of the connector every 6 months to see if there is any discoloration, deformation, loosening and other phenomena. In humid or salty places, the frequency of inspection should be higher. Connectors found to be problematic should be replaced in a timely manner so that small problems do not evolve into big failures.
Price to be rational, quality j4 connector usually in 20 50 yuan pair, excessively cheap products often have quality risks. But not the more expensive the better, some imported brands may be 3-5 times the price of domestic quality products, and the actual performance difference is not large, choose the domestic brands with complete certification, regular channel sales, the most cost-effective.
As the voltage of solar energy system gradually rises, the requirements for connectors are also gradually increasing. Currently 1500V system has become popular trend, which puts forward higher requirements for the insulation performance and voltage resistance of the connector. More advanced connector technology may appear in the future, but at this stage, MC4 is still a proven and reliable choice, as long as you master the above purchase points, you can put this important “safety” for the solar system.
