What are MC4 Solar Connectors? Importance of Solar Panels

The MC4 Solar Connector is a type of interference-fit connector with a notched lock for interconnecting solar panel cables. Compared to standard connectors, features such as water resistance and heat resistance make MC4 solar connectors ideal for use in solar panels. In this post, we will learn everything you need to know about these connectors, which are vital for photovoltaic solar energy system installations.

What is a MC4 Solar Connector?

MC4 Solar Connector is an electrical connection equipment consisting of male and female terminals to connect solar panels. MC4 solar connector is the abbreviated form of Multi-Contact 4 mm. Here 4 mm refers to the diameter of the end part to which the connector is connected.

The first official manufacturer of MC4 solar connectors was the Swedish company Stäubli Muli-Contact. These connectors sold under the name MC4 are the patented product of this company. Of course, there are many connectors on the market, especially in China, which are produced and sold under the name MC4. When buying these connectors, you should examine the safety certificates and check whether they meet the standard values.

MC4 solar connectors ensure that solar panel cables are securely connected. These connectors are usually installed by solar panel manufacturers or they can be mounted during the installation using tools such as MC4 crimping pliers.

MC4 and compatible products have been globalized in the solar industry and are found on solar panels manufactured since 2011. The voltage withstands of the new type of MC4 solar connectors can reach up to 1500 V.

MC4 is also resistant to a wide temperature range. Generally, these connectors are resistant to -40 and +90 degrees Celsius.

MC4 usually comes connected to positive and negative wires in medium and large solar panels. MC4s are mounted with MC4 solar connector crimping pliers on special cables used in photovoltaic solar panel applications known as solar cables.

How to Connect MC4 Solar Connector?

MC4 is mounted on the cable with MC4 crimping pliers. The connection is also made by connecting the female and male ends. Of course, in this connection, make sure that the connectors are fully connected. You can usually hear the connection sound when you connect them.

Solar panels have two different outputs, positive and negative. MC4 solar connectors are mounted on the panels as male and female. Solar panel connections are made by tightening the male and female together. Generally, the male connector represents the positive (+) end of the solar panel and the female connector represents the negative (-) end.

MC4 Serial and Parallel Connection

MC4s have different models for series and parallel connections of solar panels.

MC4 Serial Connection

When connecting + and – as below, the connection is made using standard MC4. Most solar panels already provide you with these apparatus in this way.

MC4 Parallel Connection

However, if the parallel connection is to be made, i.e. all positive terminals are to be connected and all negative terminals are to be connected, then you need to use the paralleling apparatus as shown in the image below. These devices provide multiple inputs and single outputs.

Importance of MC4 Solar Connector for Solar Panels

MC4 connectors protect solar panels against environmental conditions. In general, the benefits of these connectors are as follows.

• Waterproof
• Durable against oxidization and protects the cables against this
• Avoids connections from breaking in stormy conditions
• Reduces installation time as it is easy to connect
• Resistant to high temperatures
• Voltage endurance is also high

As a result, the use of these connectors is important for system safety and extending the operating life. It also reduces the maintenance costs of the system. Always use MC4 solar connectors when connecting solar panels in your projects.