Outdoor lighting creates safe, efficient, and captivating spaces. Low voltage landscape wire is essential in achieving this transformation. In this guide, we'll guide you on cable selection and installation, helping you make the most of it for your outdoor lighting needs.

Basics of Low Voltage Wire

Low voltage landscape wire is a fundamental component in outdoor lighting systems. It operates at a lower voltage than standard household electrical cables, typically running at 12 or 24 volts. This reduced voltage is a crucial safety feature, minimizing the risk of electrical shock, especially in outdoor environments where moisture is present.

Why Choose Low Voltage Wire for Outdoor Lighting?

Selecting low voltage cable for outdoor lighting is a strategic choice due to several compelling reasons:

Safety: The lower voltage significantly reduces the risk of electrical accidents, making it safer for both installation and maintenance.

Energy Efficiency: Low voltage systems are more energy-efficient than traditional high voltage setups, leading to reduced energy consumption and lower electricity bills.

Versatility: Low voltage cable can be easily buried underground or concealed within your landscape, providing flexibility in the placement of lighting fixtures without compromising aesthetics.

Understanding Wire Gauge (AWG)

Wire Gauge (AWG) is a standardized system used to measure the size of electrical wires. Common specifications range from 10 to 16, such as 12 gauge landscape wire and 14 gauge landscape wire. It is denoted by a numerical value, and the lower the AWG number, the thicker the wire. Thicker cables have lower electrical resistance, which is beneficial for longer cable runs.

landscape lighting wire

In 12v low voltage landscape lighting, using thicker cables (lower AWG values) helps minimize voltage drop, ensuring that the lighting fixtures receive the necessary voltage for optimal performance.

For example, "12/2" refers to a specific type of low-voltage cable. The "12" indicates the wire gauge (AWG), which in this case is 12 AWG, and the "2" signifies that there are two insulated conductors within the cable. Thicker cables like 12 AWG are suitable for longer cable runs and installations with higher wattage fixtures because they can efficiently transmit electrical power over extended distances with minimal voltage drop.

How to Select the Appropriate Cable Gauge?

Selecting the right cable size for your low voltage landscape lighting project is a critical step in ensuring its efficiency and performance. A smaller gauge of wire means a thicker wire conducts electricity better, but it will also be more expensive. To balance cost-effectiveness and wire performance, here are some guidelines for making the right choice:

Consider Total Cable Length and Fixture Wattage:

The total length of your cable runs and the combined wattage of lighting fixtures along each run are crucial factors in determining the appropriate cable size. The following chart illustrates the relationship between total wattage and total length, providing a reference for your cable selection. In the chart, the X-axis represents total wattage, and the Y-axis represents total length. By measuring your total length and total wattage and consulting the chart, you can identify the suitable cable size.

low voltage cable choose

For example:

16/2 low-voltage wire: Suitable for a total length of 60 feet with a total wattage of 60W.

14/2 low-voltage wire: Suitable for a total length of 100 feet with a total wattage of 60W.

12/2 low-voltage wire: Suitable for a total length of 200 feet with a total wattage of 60W.

10/2 low-voltage wire: Suitable for a total length of 300 feet with a total wattage of 60W.

Note: When the total length is 60 feet with a total wattage of 60W, it doesn't necessarily mean you cannot use a smaller gauge like 14/2. The 16/2 wire would suffice and is more cost-effective. However, if you plan to add more fixtures to the same run in the future, consider selecting a smaller gauge to prevent voltage drop issues.

Budget and Cost-Effectiveness:

In addition to considering cable size based on length and total wattage, you can also save costs through thoughtful design by minimizing cable length where possible. Strategically placing fixtures and reducing cable distances can often allow you to opt for thinner cables without compromising performance, resulting in cost savings.

Installation Tools and Steps for 12V Low Voltage Cable

Before we dive into the details of installing a low voltage cable, let's start with an overview of the tools you'll need and the key steps involved in the process.

Required Tools for DIY Installation

If you're planning to take on the installation yourself, it's essential to have the right tools on hand. Here's a list of commonly needed tools for the job:

Shovel: For digging trenches and burying the cable.

Trencher (optional): Can be used for more efficient trenching on longer cable runs.

Cable Cutter: Used to cut the cable to the desired length.

Wire Stripper: For removing the cable insulation to make connections.

Voltage Meter: To measure and verify voltage levels in the system.

Conduit (optional): Provides additional protection for the cable in areas prone to damage.

Landscape Wire Connectors: Essential for creating secure, watertight connections.

Cable Clips or Stakes (optional): Used to secure the cable along the trench or above ground.

Installation Steps

Now, let's outline the steps involved in installing low-voltage landscape lighting cable:

Step 1: Design Planning:

Start by identifying the locations where you want to install outdoor lighting. Determine the specific areas you wish to illuminate and consider your lighting objectives, whether it's for functionality, aesthetics, or safety.

Plan the cable route carefully, taking into account the layout of your landscape and the desired lighting coverage. Consider how the fixtures will enhance the overall ambiance of your outdoor space.

Step 2: Material Preparation:

Gather all the materials you will need for the installation. This includes low-voltage cables, lighting fixtures (such as path lights, spotlights, or deck lights), transformers, connectors, stakes, and any other necessary accessories.

Ensure that all the materials you have chosen meet outdoor usage standards. Pay particular attention to the cable's waterproof and weather-resistant properties to ensure long-term durability.

Step 3: Excavate the Trench for the Cable:

Using a shovel or trenching tool, dig a trench along the planned cable route. The trench's depth should be approximately 6 inches (about 15 centimeters) to provide proper protection for the cable.

Carefully lay the low-voltage cable in the trench, ensuring it remains well below the surface and avoiding any potential obstacles like tree roots or existing underground utilities.

If your cable route needs to cross walkways, driveways, or other hardscapes, consider using conduits to protect the cable from physical damage.

Step 4: Transformer Installation:

Follow the manufacturer's instructions to install the low-voltage transformer. Place the transformer near an outdoor power outlet and ensure it is elevated above ground level to protect it from moisture.

Step 5: Connect Lighting Fixtures:

Connect the lighting fixtures to the low-voltage cable. Most fixtures have connectors designed for easy installation. Follow the manufacturer's guidelines for secure and proper connections.

Step 6: System Testing:

Before covering the trench with soil, conduct a comprehensive test of the entire lighting system. This ensures that all lighting fixtures are functioning correctly and that there are no connectivity issues.

Step 7: Backfilling:

Once you have confirmed that the lighting system is operating as intended, carefully replace the soil in the trench, covering the cable completely.

Step 8: Final Inspection:

Perform a final inspection to make sure all lighting fixtures are correctly installed and functional. Check for any exposed cables or connectors that may need additional protection or adjustments.

Step 9: Maintenance:

After the installation is complete, establish a regular maintenance schedule. Periodically inspect the cables and lighting fixtures to ensure the system continues to operate efficiently and safely.

Practical Tips

Use cable clips or stakes to secure the cable in the trench, preventing it from shifting or surfacing.

Install cable connectors at the base of each fixture to create waterproof seals, preventing moisture intrusion.

Avoid excessive bending or twisting of the cable, as this can lead to damage and increased resistance.

Regularly use a voltage meter to check the system's voltage levels to ensure consistent lighting.

Follow the manufacturer's instructions and use wire connectors when making connections.


With these tools and steps in mind, you can ensure a successful and reliable low-voltage landscape lighting installation in your outdoor space.

Transformer Selection and Usage

In outdoor landscape lighting, the choice of transformers is of paramount importance. This section has provided insights into how to correctly select and use transformers to meet your lighting needs. Here are some key considerations:

Transformer Wattage

The wattage of the low-voltage lighting transformer you need depends on the total wattage of the outdoor landscape lighting fixtures you plan to connect. It's crucial to calculate the total wattage accurately by adding up the wattage of all connected fixtures.

Proper Load Rating

To ensure the transformer operates within its normal operating range and prolong its lifespan, it's advisable not to exceed 80% of its capacity. This means that if your total fixture wattage is 100 watts, you should select a transformer with a capacity of at least 125 watts (100 watts / 0.8).

Consider Future Expansion and Cost Efficiency

When selecting a transformer, think about potential future expansions of your lighting system. Choosing a transformer with a larger capacity than your current needs can be a cost-effective choice, as it eliminates the need to purchase an additional transformer later on, saving you money in the long run.

Multiple Taps Transformer

When planning the installation, take into account the number of lighting circuits you'll have. In some cases, it's beneficial to choose a multi-tap transformer. For example, the Gardenreet outdoor low-voltage transformer comes with at least 2 taps, and higher-wattage models offer even more taps. These taps allow you to create different lighting zones or circuits, providing flexibility in controlling your landscape lighting.

Example Calculation

Suppose you have 20 spotlights, each with a 5-watt bulb, all connected to the same transformer. In this case, you would need to select a transformer with a capacity of at least 125 watts (100 watts / 0.8) to accommodate the total wattage of all the fixtures.

By considering the total wattage, load ratings, and future expansion requirements, you ensure the efficiency and flexibility of your landscape lighting system.

Important Considerations

Safety is a top priority when installing and maintaining your low voltage landscape system. These tips will help you ensure system reliability and minimize potential risks.

Regular Cable Check: Every few months, inspect your cables and connections for any wear or damage. Make sure the connections are secure and snug.

Clearing Debris: Keep the cable paths clear of leaves and debris to prevent plant roots from interfering with the cables.

Dry Conditions: Protect your cables from exposure to water, especially at connection points. Moisture can lead to cable damage or short circuits.

Dealing with Damages: If you find damaged cables, address them promptly by stripping and replacing the damaged sections.

Proper Cable Burial: Ensure the cables are buried deep enough to meet local guidelines, preventing damage or accidental contact.

Use Protective Conduit: In areas where it's necessary, employ protective conduits to enhance cable durability and safety.

Wire Gauge and Maximum Current: Different wire gauges have varying maximum current capacities, as follows:

16/2 cable: Typically, the maximum current capacity is around 13 amps.

14/2 cable: Typically, the maximum current capacity is around 15 amps.

12/2 cable: Typically, the maximum current capacity is around 20 amps.

10/2 cable: Typically, the maximum current capacity is around 30 amps.

Current can be calculated using Ohm's law, where Current (Amperes) = Power (Watts) / Voltage (Volts). Therefore, it's essential to control the number of connected fixtures based on current requirements to avoid exceeding the cable's maximum current capacity.

By following these safety and maintenance tips, you can confidently use your low-voltage landscape lighting system to enhance outdoor beauty, increase safety, and extend your outdoor living space.


What is 12/2 wire used for?

12/2 wire is typically used in outdoor landscape lighting systems. It is a low-voltage cable used to connect outdoor lighting fixtures and transformers, providing the necessary power to illuminate yards, gardens, and other landscaping features. This cable is suitable for small to medium-scale lighting projects.

What is 14/2 wire used for?

14/2 wire is also commonly used in outdoor landscape lighting systems. Similar to 12/2 wire, it is used to connect outdoor lighting equipment but is typically employed in smaller lighting projects or shorter cable runs. This cable is suitable for small yards, path lighting, and landscaping features.

What's the difference between 12/3 and 12/2?

The primary difference between 12/3 wire and 12/2 wire is the number of conductors. 12/3 wire has three conductors and is typically used in situations where an additional conductor is needed, such as for a ground wire or when two separate circuits are required. In contrast, 12/2 wire has only two conductors and is commonly used for general lighting and power connections.

How many amps can 12/2 wire handle?

12/2 wire typically has a maximum current capacity of 20 amperes. This means it can safely handle currents of up to 20 amperes, making it suitable for most low-voltage landscape lighting applications.

What is the current capacity of 12/2 wire?

The current capacity of 12/2 wire is also typically 20 amperes. This capacity is sufficient to support the current requirements of low-voltage landscape lighting systems, but it is essential to ensure that it does not exceed its maximum current capacity to maintain system stability and safety.


In conclusion, this guide has provided you with essential knowledge and practical steps to set up a low-voltage landscape lighting system for your outdoor space. We encourage you to use this tutorial to either undertake the installation yourself or seek the assistance of a professional if needed.

Should you encounter any questions or require assistance in selecting cables, transformers, or designing installation routes, please feel free to leave a message or email us at customersupport@gardenreet.com. Your satisfaction and safety are our priorities.

December 24, 2023 — GardenreetLighting

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