What is an MC4 Connector: Why is it So Important?

An MC4 connector is used to connect solar panels with DC cables that carry DC power from the panels to the inverter. These connectors are the only certified and authorised options to do so. The process has to be so spotless that specialised MC4 crimping tools are needed to make this connection. 

Disconnecting them anytime will harm neither the connections nor the wires they are linked to. If you are someone who appreciates living a sustainable life, MC4 connectors are a necessity for you!  

All modern solar panels use the MC4 solar connectors. These connectors have an IP67 rating. It means they’re waterproof and dustproof. They perform well with both 4mm and 6mm solar wires. 

If you’re wondering how to use an MC4 solar connector, you’ve come to the right place! This comprehensive blog post will give you all the information! 

MC4 Connectors: Manufacturers and Top Brands

MC4 solar connectors were originally pioneered by a Swiss company called Staubli (formerly Multi-Contact). 

Multi-Contact created specifically-shaped solid copper bands for electrical contact, known as MULTILAMS. These strips produce several specified, current-carrying touchpoints that can make electrical contact.

Apart from this, several high-quality brands manufacture MC4 connectors, namely Elmex, Bizlink, and Comet.

Elmex MC4 connectors 

• They are made of flame-resistant polymer, which can withstand UV exposure. 
• Elmex panel connectors are used with photovoltaic equipment like DCDB (DC Distribution Block), inverters, etc. It is suitable for cable sizes 2.5 mm², 4.0 mm², and 6.0 mm². 

Bizlink MC4 connectors 

• They are exceptionally durable and can survive inclement weather and demanding usage. 
• They comply with current safety regulations and have a strong snap-in and lock mechanism that keeps them from detaching while under load. 
• For outdoor setup, crimping and connector assembly equipment are offered.

Comet MC4 connectors 

• They are exclusively designed for outside use. 
• Solar panels are linked together using Kenbrook Solar MC4 connectors. 
• Four solar panels, ranging in power from 10 to 400 watts, can be connected via a single MC4 T-type connector. It is weatherproof for outside use and has an IP67 rating. 
• They also have insulation to guard against electric shock. 

Did you know that MC4 has variations like MC4 connector 4 in 1 and MC4 connector 2 in 1? These varieties are used for large-scale industrial projects and they allow you to connect 2 or 4 strings of solar modules to the same DC cable. 

On the contrary, a normal MC4 connector is sufficient for residential linking.  

What are the parts of an MC4 Connector?

Five components make up MC4 connectors: a screw-on end cap, a rubber water seal, a seal retainer, metal crimp contact, and the main housing. The last two components vary on the MC4 connector’s male and female variants.

Some MC4 connectors also have detachable built-in safety clamps. They provide extra accidental disconnect safety by covering the interlocking tabs.

How Do I Install MC4 Connectors Correctly?

The cable, a male and female MC4 connector, wire strippers, wire crimps, and around ten minutes of your time is all that’s needed.

Step 1: Fitting the MC4 connector

You will see that the wire is cut more than the metal crimp connection. The ideal length for cable stripping is around 10mm and 15mm.

Step 2: Crimp the cable

Because it consistently provides a great link and secures all the components, you can employ an MC4 2.5 – 4 – 6mm crimp connector. The crimping tool is readily available online.

Step 3: Pass the crimp

The metal crimp must be crossed before the screw. Otherwise, you will be unable to remove the plastic housing without destroying it since it has a non-return clip.

Step 4: Insert the cable

You will hear a “CLICK” as you insert the crimped cable into the connection. The non-return clip secures the crimp into the plastic housing.

Step 5: Rubber washer 

You will notice that the cable’s rubber seal washer is parallel to the plastic fingers’ tip.

 Step 6: The Female Connector

To improve surface contact inside the crimp,  make a little bend in the cable. Remove insulation on the cable by 15mm to reveal the wire for crimping (similar to the male in step 2).

Step 7: Connect the cable

Once more, place the cable first before the screw nut (as in Step 3). As in step 5, check the rubber washer. Once you hear a “CLICK,” insert the crimped cable into the female housing.

Step 8: Testing

Before connecting to your solar panels, we suggest you check your wire’s integrity using the new MC4 connectors. 

Please remember that you should never unplug your solar panels from an inverter or battery or when the sun is shining on them since doing so might harm you.

Top Key Advantages of Genuine MC4 Connectors

It is strongly advised to conduct a thorough study and confirm with your solar installation company that the MC4 connectors being used are genuine. 

The market is flooded with several imitation duplicates. Avoid those at all costs!

The main advantages of using genuine connectors are as follows.

• A lot of effort is spent testing and using quality items.
• Lower maintenance costs and longer product life.
• Energy conservation and least power loss.
• Decreased heat buildup, which aids in preventing overheating.

Why Is It Best to Use Only Genuine or Original MC4 Connectors?

Connectors with flaws might impair the installation process or even start a fire. 

In addition to those above, if you utilise replica connectors rather than real ones, you can encounter the following unpleasant issues.

1. Mismatching connections can occur when non-branded items are used.
2. Poor connectivity might be the outcome. Additionally, it may result in a spike in temperature, which can overheat the system. 
3. It will also let water in, which could start a fire.
4. A faulty connector enables rain and dust to enter. In that case, the dust may reduce the connector’s insulating qualities.
5. The system can fail, and a fire may result in losing a home or a person’s life.
6. If the system is malfunctioning, rework will be necessary.

The rigorous testing in authentic MC4 connectors has not been applied to non-genuine connectors. 

Conclusion 

Only original MC4 connectors meet the safety benchmarks. Using duplicates invite all sorts of dangers: fire, short circuits, and whatnot. So, when you install a rooftop solar system, ensure that the connectors are genuine. 

FAQs

Q. What is the full form of MC4?

Solar panel connections frequently employ single-contact electrical connectors called MC4s. 

The manufacturer Multi-Contact is indicated by the MC in MC4, and the number 4 denotes the contact pin’s 4 mm diameter.

Q. Which is the positive side of the MC4 connector 4-in-1?

MC4-equipped modules should be wired in series. The DC positive (+) wire is one, while the DC negative wire is the opposite (-). 

Most of the time, the positive wire is connected to the female MC4 connection, while the negative wire is connected to the male connection. 

Q. Are all connectors for the solar panels the same?

Solar panel connectors come in male and female varieties. There are many connectors, but the main ones are MC3, MC4, and Tyco Solarlok. 

They come in various forms, including T, U, X, and Y. The MC4 connectors, however, are the best ones.