Faraday disk, the first homopolar generator.

What is voltage loss and how to avoid it

Low voltage outdoor lighting troubleshooting

When you are low voltage outdoor lighting troubleshooting, voltage drop is a key element to check. Of course there are obvious items to check such as bad connections. But when it comes to ensuring your system will last a lifetime, managing voltage loss is key.

Voltage loss is phenomenon that occurs when electricity loses voltage as it travels down a wire. Your voltage drop will depend on how long your wire is, the thickness of the wire and the number of fixtures on the circuit.

Create an efficient layout

The first thing to check when low voltage outdoor lighting troubleshooting is your layout. Daisy chain layouts are more susceptible to low voltage power loss.
Hub vs Daisy Chain Layout


Your fixture should be wired in ‘zones’. This allows you to keep all fixtures in an area the same relative distance from the transformer.  Group the fixtures close to the transformer (30′ or less) together, then group the ones that are slightly farther away (30′ to 60′) and finally group the ones the farthest distance  (60′ to 100′).

 Use hubs when possible

Try to use a wheel and spoke method of connecting the fixtures in each zone. Instead of running a ‘daisy chain’ wire from fixture to fixture have a central connecting point so the fixtures are all relatively the same distance from the transformer. If you find yourself forced to daisy change limit the number of fixtures on the chain.

Thick wire reduces voltage loss

Wire Gauge
Use a wire gauge to determine the thickness of your wire.

The temptation is to use 14 or even 16 gauge wire for your new system. This may work fine for a small do-it-yourself system from a big box store but this is not the cable to use in a larger-scale professional system.

Use at least 12-gauge wire and consider using 10-gauge on your longer runs (100′).  The thicker cable will not have as much voltage loss as thinner cable. In other words your voltage drop on the longer runs will be less as you increase the thickness of the cable. Note: The higher the gauge number the thinner the wire.

Put fewer fixtures on the long runs

You don’t want both a long run and a large number of fixtures on that run. If you have a large number of fixtures (or a high wattage draw) in a zone that is a long way from the transformer, break that zone into two runs. Separate the fixtures into two groups and create a hub for each.

Locate the transformer in a central location

Do your best to put the transformer as close as possible to the center of your system. While this may not be possible due to your high voltage power source, the closer to the center you are the less power drop you’ll have. A good rule of thumb is to put the transformer halfway between the two farthest groups of fixtures. Diagram your runs to these fixtures and work your way back to the transformer grouping the mid-length sections and finally the zones closest to the transformer.

Use a multi-tap transformer

You may not find a multi-tap transformer in your local home center but if you’re building a comprehensive outdoor lighting system chances are you’ll benefit from a multi-tap transformer.

Multi-tap transformers have terminals giving voltage output ranging from 12 volts up to 18 or more. Your longest runs, with highest power wattage requirements may necessitate that you power that run with 16 volts. Because of the line loss and high wattage requirement, by the time the power gets to the farthest fixture it may be getting 4 less volts at the fixture. Using the 16-volt tap solves this problem and ensures the best looking illumination and longest-lasting bulb.

Use a multimeter

Inova Multimeter
Multimeters like this Inova can be as little as $20. This tool is imperative when low voltage outdoor lighting troubleshooting.

If you are installing a system larger than a small do-it-yourself system you will need a multi-meter.

Without the use of a multimeter you’ll never know what type of voltage loss you’re getting. This will result in poorly performing fixtures and less life from your bulbs.

One of your first investments should be a multimeter. You can find them in local stores or online for as little as $20 on Amazon.

Call in a professional

Low voltage outdoor lighting troubleshooting is something most homeowners can handle if they have the tools and know-how. If you want a comprehensive system that is well balanced and will last a lifetime the above tips will help. If you’re not inclined to devote the hours and material to design and balance a system, there are local firms who will provide an optimally design system for you.

If you’d like for a professional to come out for a visit please contact us. We’ll be right out for a no-obligation consultation. We’ll tell you what we think and if you’d like an estimate we’ll provide one quickly and back it up with our lifetime warranty on all parts and installation.

Visit our web site at www.AbulousLighting.com,
call/text 662-Abulous (662-228-5687)
or email TheBoss@AbulousLighting.com

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