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Technical Light Information

Troubleshooting Christmas Lights

There's no question that seeing a few bulbs burned out is frustrating and it's something everyone experiences. The good news nowadays is that even when one bulb goes out, it won't cause the rest of your strand from illuminating. If you do see a few burned out lights, here are two simple steps to get that entire strand working again.

  1. 1. Check each bulb to see if they are fully inserted into the socket

    For many people, this is routine when putting Christmas lights up. This quick light strand check can help you find burned out lights that may need to be replaced. For the majority of strands, they will stay lit even when a bulb is out, but for some, the strand may not light up. For lights where you can take the bulb out of the socket to stay lit, you will need to have the bulb either fully in the socket or fully out of the socket. If it is not fully in or out, it will cause a light set to not be lit.

  2. 2. Are the bulb wires making proper contact?

    Remove the bulb and adjust the wire if necessary.

    If you're still having some issues, you may want to try out our Light Keepers tool, or another light testing item to help you out.

LightKeeper Pro

It's important to make things easy and time-efficient when you begin to decorate for Christmas. Everyone is going to deal with a few burned out bulbs, but The LightKeeper Pro is a powerful tool that will make fixing strings of lights easy and save time. This light tool can detect faults in a wire, clear issues that prevent strings from staying lit after bulbs burn out, and even test bulbs and fuses for quality. All of this is available in a single handheld device. Take a look at what a few of the basic uses are for this device.

  • Quick Fix Piezo Trigger

    This simple to use system helps identify faulty bulbs and repair problems with defective shunts by sending an electrical pulse through the defective light strand.

  • Continuity Detector/Voltage Detector

    When the LightKeeper Pro's Continuity Detector/Voltage Detector scans a defective light set, it will indicate where a power interruption occurs, helping you find the area needing repair.

  • Bulb and Fuse Tester

    The Bulb Tester, built into the top of the LightKeeper Pro, offers a third way to repair your light sets. You can individually test miniature light bulbs. Working bulbs inserted into the tester will illuminate immediately, indicating they are functioning properly. The Fuse Tester is designed to check 3 amp fuses supplied with most miniature lights. Place the fuse in the Fuse Tester. If the fuse is good, the red light on top of your LightKeeper Pro will illuminate.

  • Bulb Puller/Remover

    This tool makes it easy to remove those bulbs from the light strands. Two different bulb pullers are designed into the LightKeeper Pro: a Conventional Puller and a Hook and Pull remover.

  • Storage Organizer

    Keep those extra light bulbs organized in the convenient built-in storage compartment. It has slots for 2.5-volt bulbs, 3.5-volt bulbs, and fuses.

  • LED Light

    Built-in light makes it easy to work in the dark.

What are Volts, Amps, and Watts?

  • Voltage Calculations

    Volts (V) measures the force (strength) of electricity.

    Voltage = wattage / amperage

    Average US Household is 110-120 volt service.

  • Amperage Calculations

    Amps measure the amount of electricity used.

    250 Mini 2.5 volt bulbs = 1 amp

    Wattage / Voltage = Amperage

    The average outlet in a US home are 15 or 20 amps.

  • Wattage Calculations

    Wattage is the best way to tell you how many sets of Christmas lights you can connect end to end.

    Watts measure the work electricity does per second.

    Amps x voltage = wattage
    # of bulbs x bulb wattage = total wattage

  • How many volts, amps, and watts are in incandescent mini light sets?

    35-light Mini Set = 120 V, .12 amps, 14.4 watts

    50-light Mini Set = 120 V, .17 amps, 20.4 watts

    100-light Mini Set = 120 V, .34 amps, 40.8 watts

    NOTE: The average outlet in a home has 20 amp service.

    NOTE: Voltage is never more than 120 V for these light sets. The standard house service is usually 120 and is the industry standard for most mini light sets and complies with UL testing. We list bulb voltage to ensure consumers use the correct replacement bulbs.

What Type of Fuse Does My Light Set Use?

  • Incandescent Mini Light Sets use 3 amp fuses.
  • Heavy Duty light sets 5V use 3 amp fuses.
  • C7, C9 light sets use 5 amp fuses.
  • G40, G50 light sets use 5 amp fuses.
  • Most non-replaceable LED sets use 3 amp fuses.

It is always best to check the packaging or labels to find out what type of fuses your Christmas light set or Christmas tree uses.

Extension Cord Tips

As Christmas lights begin to go up, extension cords begin to come out. These handy cords come in a variety of different sizes and colors, but it's important you use them properly. From making sure you only use indoor cords for your indoor Christmas displays to keeping them tucked away. We put together a few tips for you when you begin to use these extension cords for your Christmas lights. Always make sure to check the labels and packaging for further information.

If possible, try to plan out how much electricity you will need your extension cord to handle. This will allow you to have the proper extension cords as you begin to decorate your home. If you're someone who loves creating those large outdoor displays, you will most likely need a heavy-duty extension cord. In this case, both the length and gauge are important. The higher the gauge, the thinner the wire or cord, and the less amperage it can safely handle. Keep in mind that the longer a wire becomes, the less amperage it can hold. Use shorter extension cords as much as possible.

The Difference Between Standard and Commercial Christmas Lights

Generally, standard lights have a thinner, lighter wire connecting them. They are slightly less hardy and resistant to damage, and in general have a lower limit for the number of bulbs you can connect end-to-end.

Commercial lights are designed specifically to meet guidelines set by professional decorators. They are more durable and bulkier than standard lights. Some, not all, are made in a sealed single-cast construction making the bulbs non-removable. Despite these bulbs not being able to be removed, they are more durable and will last through inclement weather. On average, commercial lights can have more lights connected end-to-end than standard lights. With that said, it's important to know that commercial lights have less space between bulbs, finding yourself needing more sets.

Each light set has its advantages, so decide for yourself which would work best, based on your needs for the year.

Light Timers

Hitting that switch to turn on and off your Christmas lights is such an easy task, but one that many people can easily forget. Electrical timers make sure those beautiful Christmas go on and off when you want them to. Electrical Christmas light timers come in a variety of forms and levels of complexity. From the basic ones that turn on your lights for a specific amount of hours to the more complex models that run on schedules and times of days. Whichever models suit your needs, you can be sure that you will never forget to turn on or off those Christmas lights again.

A similar device that we offer is the remote control activator. This device can be activated by a wireless remote, allowing for extra freedom in controlling devices and lights that normally would be in an inconvenient place to activate.

UL and CSA Approved Lights

  • What does UL mean?

    Underwriters Laboratories Inc. (UL) is an independent product safety certification organization that controls and monitors lighting rules and safety regulations. A "UL-approved" designation means a product has been approved by this agency. UL has developed more than 1000 Standards for Safety. Its Standards for Safety are essential to ensuring public safety and confidence, reducing costs, and improving quality. Millions of products and their components are tested to UL's rigorous safety standards with the result that consumers live in a safer environment than they would have otherwise.

  • What does CSA mean?

    CSA stands for Canadian Standards Association. CSA certifications are used and accepted across North America and around the world, on over 1 billion products. And that number continues to grow.

    In the United States, CSA International is accredited by the Occupational Health and Safety Administration (OSHA) as a Nationally Recognized Testing Laboratory (NRTL). Generally speaking, all OSHA accredited laboratories conduct their tests against the same sets of U.S. standards and codes, regardless of who authors or publishes them. CSA International tests are applicable to U.S. standards, which include ANSI, UL, CSA, NSF, and others.

    In Canada, CSA International is accredited as a Certification Organization (CO) and as a Testing Organization (TO) by the Standards Council of Canada (SCC).