Single-contact electrical connections are what MC4 connectors are all about. Connecting solar panels is a popular application for them. The abbreviation for “Multi-Contact, 4 millimetres” is “MC4”. In the field of renewable energy, this is the norm. Panel strings can be quickly assembled with the use of an MC4 connector. In today’s solar market, MC4 connectors and devices that are compatible with them are employed universally. Larger solar panels typically use MC4 connectors as standard. Multi-Contact, the authorised producer of MC4 connectors, produces these. Solar panels have plastic spherical housings with a single conductor that is paired with a male conductor. MC4 connectors have a notched interlock that allows them to terminate and prevent accidental disconnection.
Before, solar modules had a junction box on the back where the installer had to physically connect wires to the module’s positive as well as negative terminal pins. Even though this technique is still in use, it is quickly becoming obsolete. In order to simplify and speed up the wiring of a solar array, most modern solar modules employ MC4 connectors.
There are male and female varieties of MC4 or Solar PV branch connector in India, and they snap together for easy use. They are approved by Electrical Safety Authorities as meeting the standards for electrical connections and are UL-certified to ensure safety. The MC4 connectors are weather-resistant and inconveniently unpluggable thanks to their locking mechanism. A specialised MC4 unlocking tool is required to disconnect the connectors.
How to wire the modules equipped with MC4?
Connecting many solar panels in series using MC4 connectors manufactured by one of the leading Solar PV connector manufacturers is a breeze. You can see that the first module has two wires coming out of the junction box if you take a look at it. With the direct current (DC), one wire represents positive voltage (+), as well as the other, represents negative voltage (-). The male MC4 connection is typically connected to the negative lead and the female to the positive. Check the junction box?s markings or use a digital voltmeter to confirm the polarity, as this is not always the case. Wiring the modules in series entails joining each module’s positive terminal to the negative terminal of the next module. The male plug can be plugged straight into the female socket.
Both modules’ leads have been linked at this point. By doing so, we raise the circuit’s overall voltage. Modules with a maximum power rating of 18 Vmp, for instance, when connected in series, will produce 36 Vmp. When three modules are linked in series, the resulting voltage is 54 Vmp. In a series circuit, the maximum power current (Imp) will remain stable.
In a parallel circuit, the positive and negative terminals must be joined. By employing this technique, the maximum power current (Imp) can be raised while the voltage remains unchanged. Assume, for the sake of argument, that the maximum power point voltage and current for your modules are 18 Vmp and 8 Imp, respectively. Two of them wired in parallel would have a total amp draw of 16 Imp, with the voltage staying at 18 Vmp. There is some supplementary gear required for parallel wiring of two or more modules. The simplest solution is to utilise MC4 multibranch connections if you’re only connecting two modules. Many of the manufacturers, as well as exporters of Solar PV branch connector in India, suggests using a two-module MC4 connector.
We utilise multibranch connections because it is impossible to join together a pair of male or female connectors. Specifically, we have two distinct multibranch connectors. One variety takes in two of the male MC4 connectors and spits out another male MC4 connector. The other variety has an output female MC4 connector and takes in two female MC4 connectors. From four wires (two positives, two negatives), you’ve cut down to two wires (one positive, one negative).
If you conduct the paralleling process on more than two modules for a device is known as a PV combiner box. The combiner box serves the same purpose as the multibranch connectors, so you may get rid of them. Two modules can be connected in parallel using multi-branch connectors. It is necessary to utilise a combiner box if you wish to join two or more strings or modules concurrently. Depending on its electrical capacity and physical size, the combiner box will determine the maximum number of modules it can join together.
Selecting and using MC4 extension cords is important whether you’ve coupled your modules using multi-branch connections or a combiner box.
Using MC4 Extension Cable:
There’s no need to feel stupid if you can’t figure out the extension cables of MC4. Working with solar modules can be daunting if you’ve never done so before. For starters, you’ll have to dig deep into your pockets to purchase one. We all know the feeling of buying a pricey cable only to have to cut it since it was bought in a shorter length than needed. Since we cannot accept returns on cut cables, it is imperative that you have a thorough understanding of how to select the proper length and use the cables to join your panels.
To a large extent, an MC4 extension cable can be compared to a standard electrical extension cord. The male end of an extension cable plugs MC4 into the male end of another device, much like an ordinary extension cord. They come in a wide variety of lengths, starting at 8 feet and going up to 100 feet. Power from the series connection of the two modules must be transported through MC4 cables to the location of the electrical devices. Since RVs and boats typically employ systems with two modules, the extension cables can be used throughout the whole length of the vehicle.
It is usually impractical to utilise an extension cord when connecting solar panels to a home or lodge because of the great distance the wire must travel. Those cases call for the usage of extension cables that are needed to link the panels over a combiner box. Rather than using pricey MC4 cables, you can instead save money by installing cheaper wiring within the electrical conduit, allowing you to cover longer distances.
Let’s assume you need 20 feet of cable to connect your modules to the power supply. Many Solar PV connector manufacturers?suggest that it is not necessary to use multiple cable extenders. Ideally, you would purchase one of our extender cables, which are 50 feet in length. Don’t forget that the positive lead male on one solar module is already connected to the negative lead female on another solar module.
It will take a male and female 20-foot wire to reach your equipment from here. In order to accomplish this, a 50-foot extension wire is shortened to 25 feet. In that case, you’ll have a male-connected cable that’s 25 feet long and a female-connected wire that’s the same length. Both leads of the solar panel can be connected this way, and the length of the cable is sufficient for reaching the intended location. However, there are situations in which severing the wire in two is not the best option.
Depending on where the combiner box is placed, the distance from one end of the box?s panel string could be greater than the distance from the other end of the panel string. For this reason, the extender cable should be snipped so that both ends can still touch the combiner box along with some of the spare room. This figure illustrates one possible outcome of such a situation:
It is sufficient to select a length that, after the cut, will allow for termination into the combiner box in systems employing this component. Once the ends have been cut, the insulation can be removed so they can be connected to circuit breakers or a bus bar.
How to disconnect MC4 Connectors?
Female MC4 connectors include slots on one side that the tool’s two projecting posts can go into. When you do this, the locking mechanism of the male connector is disengaged and the connection can be severed. You can get your hands on not one, but two of those disconnect tools right here. Should the need arise, two separate tools will be required to disassemble the connectors. Nonetheless, this is rarely mandatory. Usually, a single instrument is sufficient.
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