Today we discuss the best cable for solar panel. This information will protect you and your panels and enhance its performance. Cables with very thin insulation are often colored foil to identify the voltage and wattage of the cable.
Why is the right cable for solar panel so expensive?
The best metals for electrical cables are silver, copper, and aluminum. Silver is the ideal option, but can be very expensive and would not be financially viable for home solar systems. Copper is the next best option and much more affordable than silver.
Aluminum wire is often commercially available as a low-cost alternative. Copper-clad aluminum is also available to seduce the frugal shopper, but should be avoided at all costs.
If you’re running a short-term test setup, you can use a lower-cost cable for the solar panel just to test your proof of concept, but for long-term installations, pure copper cable is best.
Solar cables are made of thin strands of copper wire to ensure flexibility and maximum current carrying capacity with the lowest resistance. The stranded wire carries the flow of electrons better than a solid wire of the same gauge.
Types of cable for solar panel
Many of our customers ask us, “can I use any wire for solar panels?” The short answer is no! DC cable for solar systems is produced in various thicknesses and is rated by amperage at a certain diameter (gauge) and temperature.
The bigger the diameter of the strands of copper wire, the less resistance the electric current will have traveling from the solar panels to the charge controller.
The design of your solar installation will consider how far the solar panels are from the charge controller and what the voltage drop will be at that distance.
Can I use a regular cable for solar panel?
Do not use standard cables. They will not handle the high currents associated with a solar panel system because they are not rated for outdoor installation and direct exposure to sunlight.
Speaking of what wire to use for solar panels, we should let you know you should use cables made specifically for outdoor installation, such as MC4 connectors or copper grounding lugs, to ensure they will last a long time.
If you have access to a welder, you might also consider sealing all of your connections with metal-to-metal adhesive because it will prevent corrosion from forming over time.
That said, many people don’t bother to seal their cables, and sometimes it doesn’t matter as much as you might expect because stainless steel cable is already resistant to corrosion.
Can THNN cable be used for solar panels?
No, THNN cable has a much larger insulating layer on the conductor, which is not needed for the lower voltage of a solar panel application.
That insulation would block the flow of electrical current too much to be useful in a solar panel array. THHN cables have a small insulating layer on the conductor, and that works fine for low-voltage solar panel setups.
However, this could cause some problems. The solar panel voltage is approximately 15 volts, but the public grid has 120 or 240 volts of AC electricity.
This means that there is going to be a big difference in electrical potential between the wiring in your home and your solar panels, which can cause electricity to form in the air from wire to wire if the insulation is not thick enough to avoid that.
Can I use an ACSR cable for solar panel?
No. ACSR cable has aluminum conductors, but those conductors are much thicker to compensate for the lack of electrical current flow from an aluminum conductor compared to copper.
You can do calculations just like you would for THHN cable to make sure your cables have enough wattage capacity for your application (in this case, a solar panel system). These cables also have different insulation, usually a colored layer to identify the cable’s wattage and voltage.
Can I use Romex cable for solar panels?
No. For various reasons, mainly because all conductors have some resistance, if you are wiring your house with Romex (which has NM-B insulation), there will be too much electricity loss through the temperature rising, which can cause problems like fires if there is nothing done.
Also, the thin NM-B insulation is not designed to withstand the heat of a solar panel system, so it is likely to deteriorate over time.
Also, not every type of NM-B has the same level of resistance to fire. For example, when exposed to flame, Romex only lasts for about 3 minutes.
If you use Romex in a solar panel wiring setup, your wires will likely melt and catch fire after being exposed to sunlight for a few minutes.
You may have asked yourself “can I use normal wire for solar panel?” before reading this article, but we hope we’ve given you the answer and have prepared you to choose the best solar cable for your solar energy system. You may still have more questions like “can I use ac cable for solar panel?” in which case you need to contact our technicians at Pas Solar, where you can buy solar material in Dubai.