Photovoltaic connector is a transportation hub that effectively connects the key components of the solar power generation system. It can be called the main artery of the solar power generation system. The connection with the junction box, components, inverters, etc. requires the use of photovoltaic connectors.
According to the "Review and Analysis of Factors Affecting Photovoltaic Power Generation" report released by the "Solar Bankability" project team of the EU Horizon2020 program, among the power generation revenue losses caused by the risk of failure of the TOP20 technology in the power station, connector damage and burnout ranked second. bit. How to install photovoltaic connectors correctly is a problem that cannot be ignored in the construction process.
The root cause of the failure of the connector is that in the case of current flow, the increase in resistance leads to an increase in temperature rise and exceeds the temperature range that the plastic shell and metal parts can withstand. In addition to the product quality itself, improper installation is one of the main factors causing the increase in resistance.
01
Performance requirements for photovoltaic connectors
First, the photovoltaic connector should have good conductivity, and the contact resistance should not be greater than 0.35 milliohms.
Second, it needs to have sufficient safety performance to ensure the safety performance of solar cell modules. The environment and climate in which solar energy equipment is used are sometimes in very bad weather and environment. Therefore, it must have waterproof, high temperature, corrosion resistance, high insulation and other properties, and the protection level should reach IP68.
Third, the solar connector structure should be firm and reliable, and the male and female connectors should be correctly inserted. For the MC4 connector connected to a 4mm² cable, when carrying a current of 39A, the temperature should not exceed the upper limit temperature of 105 degrees. MC4 connector is a single-core connector, divided into male and female, has many advantages such as good sealing, convenient connection, convenient maintenance and maintenance.
02
PV Connector Installation cautions
1. Purchase of plugs
Pay attention to the product quality, including the size compliance of the internal metal conductor, the material thickness, elasticity and coating should meet the ability to carry large current and good contact, the plastic of the connector shell should ensure that the surface is smooth and no cracks, and the interface is well sealed. When installing the component connector, avoid exposure to sunlight and rain, so as to avoid aging of the connector, corrosion of the internal connector and cable, increase in contact resistance, or even ignition, resulting in a decrease in system efficiency or a fire accident.
Solar connectors, in the PV power plant is not small, recently, connected to a few customers asked about solar connectors, Slocable looked up some information, to H4 and MC4 connnectors. For example, the two commonly used brands, for everyone in the choice of connector to provide some reference. Although the appearance of MC4 and H4 is similar, but the contact size, material is somewhat different, plug together, long-term operation will lead to contact heat, failure. There are many kinds of connectors on the market, also said to be compatible with MC4 or H4, but the recommendations in the same connection do not mix different brands of connectors !
2. The crimping cable must use professional crimping toolkit.
The stripping line length is recommended to be around 7.8 mm. Too long will expose too much wire is not conducive to electrical safety, too short will lead to wire and contact area is too small, unstable.
In the installation of photovoltaic connectors, 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 installers should be trained in crimping operation.
For the MC4 connector, when pressing the wire, do not press down the limit clasp as the pressing sheet, otherwise, can not fix the position of the contact in the insulation.
3.Connectors in Inverter Accessories
The connectors in the inverter accessories are equipped according to the DC terminal of the inverter itself. Therefore, in order to ensure the long-term reliable operation, it is recommended to use the connectors provided by the inverter manufacturers to connect the DC Group and the inverter.
Although the connector is small, but do a good job in the power plant, to ensure that the safe operation of the plant no small matter. We need to do every detail of photovoltaic efforts to ensure that the people of 25 years of sustainable power generation benefits.
Since its establishment in 2008, Slocable has always focused on the research and development of safe and efficient photovoltaic products, striving to promote the healthy development of the industry.
For more information on pv cable connectors, please feel free to call Slocable at 86-769-22010201. You can also email us at pv@slocable.com.cn.
