What Size Wiring Should I Use For My LED Lighting?

November 25, 2020 2 Comments

What Size Wiring Should I Use For My LED Lighting?

LED light systems are not complicated. In fact, due to the small amount of electricity or current they utilize, you can practically use just about any wire that you can find. Of course, you have to consider a few things to get the right size wiring for your 12v LED lighting.
Should You Get a Solid Core or a Stranded Wire?
There are two kinds of wires: solid core and stranded. The solid core contains a single solid conductor, which is usually copper, and a plastic insulating jacket wraps this conductor. On the other hand, a stranded wire usually contains several conductors in a bundle, with an insulating jacket wrapping everything.
Stranded wire is flexible, but it can be a bit tricky to work with. It requires some soldering to stiffen it up so you would be able to jam it in a connected. On the other hand, the solid core is a bit more flexible, and it is easier to make connections with this wire. Both wires would work with your LED lighting, but it is easier to use the solid core.
What is the Proper Gauge?
You need to know and select the right gauge for your wire system – the bigger the better. The problem with big wires though is it can be a bit difficult to terminate, and it is not as flexible as thinner ones. Fortunately, LED lights do not draw a lot of current so you don’t have to use large wires.
When it comes to choosing wires, you need to look for the AWG designation. AWG stands for American Wire Gauge. This is the rating for wire work. Curiously, the number indicates the wire size – the smaller the number, the larger the wire. So, 18-gauge wire is smaller than a 16-gauge wire.
What Should You Consider When Selecting Your Wire?
You need to consider two things when selecting wire for your LED system: voltage drop and wire ampacity.
Copper is an excellent conductor of electricity, but it does have some inherent issues. You would see more resistance on your circuit when the cable is longer. This resistance is measured in ohms. The resistance also increases when the wire gets smaller. This is due to a much smaller area, which the electrons can flow through.
You can expect the voltage to drop when the resistance increases. If you have a small wire that is considerably long, you can expect that the 36 voltage that your driver is supposed to put out will drop to about 35 volts. This drop could result in constant changes in your voltage system, which inadvertently causes large draw in the current. So, learn to determine your correct wire gauge before deciding on any size and length.
Another consideration is the wire ampacity. You need to make sure that the wire you choose can handle the amount of electricity that will be coursing through it. A small wire can heat up easily due to resistance, and this can be quite dangerous. This can melt the wire’s jacket. Worse comes to worst, this can start a fire.
The majority of LED setups in homes have short wire runs. They are also connected in series with only a low amount of current flow. You can get away with using a small wire, but if you trying to install several lights, driving them hard in parallel, you should think twice about using a small wire. You could end up with a big amount of current that will need to course through your wire. Check out the handling ability of different wire gauges.

different wire gauges

Step-by-Step Guide on Determining the Correct Wire Gauge
1.    Compute the total wire length you need for the connection like a LED strip.

2.    Calculate the amount of current that could flow through the wire. To do this, compute the total length of LED strips connected to the power supply, and then multiply this number by the wattage per foot. So, for example, a LED light consumes about 4.4 watts per foot. If you going to use about 16 feet, you multiply 4.4 by 16, and you get 70.4 watts.

3.    Divide the total wattage computed on the previous step by 12 to get the total amps or current. So, it would be 70.4 watts divided by 12, you get 5.87 amps.

4.    Refer to the chart below to find the right wire gauge. It is at the intersection of the amps and feet. So, for 50 feet and 5 amps, the correct wire gauge is 10. Remember that the wire itself draws current, so if you are using a longer wire, make sure to use the thick ones. On the scale below, the lower number the thicker the wire.

american wire gauge

Wire Gauges and Sizing
Most household lighting fixture, as well as many appliances, requires about 12- or 14-gauge wire. This is usually indicated as a number and a dash and then another number. For example, 12-2 or 12/2.
The first number, 12, indicates the wire diameter while the second number determines the number of wires the cable contains. Cable refers to sheathed wire bundles, which are usually enclosed in plastic insulation.
Wire Color Coding
Another type of wiring standard that you need to consider is the color of the sheath or insulation that encloses the wires or cables. The color would often indicate what kind of wire is encapsulated inside.
Black or red insulation indicates that there is a live or hot wire inside. A white or brown cover indicates that there is a neutral cable or wire inside. A yellow or yellow/green cover means that there is a ground wire inside.
Please remember that current or electricity can also pass through a neutral wire, so make sure to observe safety procedures when handling wires. Turn off your circuit breaker or light switch before working on any installations.
Most people would likely recommend using a solid core 18-gauge wire for your LED lights. The cost difference between this wire size and a much smaller cable is negligible, and 18-gauge is about as big as you can go if you would like your wires to fit into most holders or terminals. This wire size is capable of handling much more than your average system.

wire connectors

If you are going to install several 12v LED lighting with dimming options, you might want to grab wiring connectors, which can help you with your wiring. Connecting with ease and safety is easy with 12VMonster DC Connectors, which is suitable for all low voltage DC wiring connections. These connectors feature dual wire terminals, both positive and negative. They can facilitate easy wiring installation, and they can be used for fishing boats, motor homes, RVs, buses, vehicle systems, solar systems, and wind systems. With these connectors, you can eliminate messy wiring once and for all.


For a even more power packed guide to all things wiring - check out this Ultimate Guide: Wiring, 8th Updated Edition (Creative Homeowner) DIY Home Electrical Installations & Repairs from New Switches to Indoor & Outdoor Lighting with Step-by-Step Photos (Ultimate Guides)

2 Responses

Brad Blomburg
Brad Blomburg

June 29, 2022

This looks like a pretty Cool way to lower the electric bill


June 29, 2022

I plan to drill my corner shower canopy and install some 12 volt marker LED lights like what goes on vehicles. I will install at least 20- to 40 of these and wondered what watt remote control i should use. Would a 120 watt relay control be ok for up to 60 of these bulbs as they are about .o3 amps or .04 each. If i can find the voice control for four different color lights i might try the wifi approach but i think i need some advice on that how to set it up economically.

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