GKOLED 120W (120V-12V)

GKOLED 120W Low Voltage Transformer User Manual

Model: 120W (120V-12V)

Brand: GKOLED

1. Introduction

This manual provides detailed instructions for the installation, operation, and maintenance of your GKOLED ETL Listed 120W Low Voltage Transformer. This outdoor power pack is designed to convert standard 120V AC household voltage to a safe 12V AC output, making it ideal for landscape lighting systems. It features an integrated photocell and timer for automated operation, ensuring energy efficiency and convenience.

Key features include:

  • ETL Listed for safety and CEC Level VI Certified for efficiency.
  • Integrated photocell and timer with 11 preset operation modes.
  • Fully encapsulated Toroid core for reliable, efficient, cooler, and quieter performance.
  • Heavy-duty steel housing for durability against various weather conditions.
  • Dual isolated 12V AC outputs for flexible landscape lighting control.

2. Safety Information

Please read and understand all safety instructions before installing or operating this transformer. Failure to follow these instructions may result in electric shock, fire, or other hazards.

  • WARNING: Risk of electric shock. Install the transformer at least 1 foot (30 cm) above ground level.
  • Do not immerse the transformer in water.
  • Ensure the power supply is disconnected before making any connections or performing maintenance.
  • Use only low voltage landscape lighting fixtures with this transformer.
  • Do not overload the transformer. The maximum suggested load is 100W, considering wire losses.
  • All wiring should be performed by a qualified electrician or in accordance with local electrical codes.
  • Connect the transformer to a GFCI (Ground Fault Circuit Interrupter) protected outlet.

3. Product Overview and Components

The GKOLED 120W Low Voltage Transformer is designed for robust outdoor use. Familiarize yourself with its main components:

Diagram of GKOLED 120W Low Voltage Transformer highlighting its components
Figure 3.1: Product Components. This diagram illustrates the key parts of the transformer, including the durable steel housing, integrated photocell, 11 power modes with simple interface, 2 terminal outputs, standard 120V Type B plug, and 3.3 ft. 18 AWG power cord. Mounting hardware is also included.
  • Durable Steel Housing: Provides protection against outdoor elements.
  • Integrated Photocell: Automatically detects dusk and dawn for light activation.
  • Control Panel: Features a digital display and up/down arrows for selecting operation modes.
  • Terminal Outputs: Two sets of 12V AC output terminals (COM and 12V) for connecting landscape lighting wires.
  • Power Cord: A 3.3 ft. 18 AWG power cord with a standard 120V Type B plug for connecting to a power outlet.

4. Setup and Installation

Follow these steps for proper installation of your low voltage transformer:

  1. Choose a Location: Select a suitable outdoor location near a GFCI protected 120V AC outlet. The transformer must be mounted vertically at least 1 foot (30 cm) above ground level to prevent water ingress and ensure proper operation of the photocell.
  2. Mount the Transformer: Use the included mounting hardware to securely attach the transformer to a wall or sturdy surface. Ensure it is level and firmly fixed.
  3. Wire the Lighting System:
    • Strip approximately 1/2 inch of insulation from the ends of your low voltage landscape lighting wires.
    • Connect the wires from your lighting fixtures to the 12V AC output terminals (COM and 12V) on the bottom of the transformer. Securely tighten the screws to ensure a good electrical connection. The transformer provides two independent output channels for flexible wiring.
    • Ensure the total wattage of all connected fixtures does not exceed 100W to prevent overloading the transformer.
    Diagram showing two steps for easy installation of the GKOLED transformer
    Figure 4.1: Easy Installation Steps. Step 1 shows connecting wires to the 2 terminal output ends, securely tightening screws. Step 2 shows plugging in the transformer and programming it using the up/down buttons.
  4. Plug In: Once all connections are secure, plug the transformer's power cord into the GFCI protected 120V AC outlet.

5. Operating Instructions

The transformer features an intuitive interface with a digital display and up/down buttons to select from 11 operation modes.

Diagram illustrating 11 optional operation modes for the GKOLED transformer
Figure 5.1: 11 Optional Operation Modes. This image details the various modes, including "O Always on", "A Automatically On at Dusk and Off at Dawn", and timed operations (1-9 hours after dusk).

Selecting Operation Modes:

Use the Up and Down arrow buttons on the control panel to cycle through the available modes. The selected mode will be displayed on the digital screen.

  • "O" (Always On): The lights will remain on continuously.
  • "A" (Auto Dusk-to-Dawn): The integrated photocell will turn the lights on automatically at dusk and off at dawn.
  • "1" through "9" (Timed Modes): The photocell will turn the lights on at dusk, and the timer will turn them off after the selected number of hours (1 to 9 hours).

Photocell Sensor:

The integrated photocell provides reliable dusk-to-dawn functionality. It includes a 30-second tolerance to prevent accidental turning on or off due to temporary light or shadow changes.

Image showing the photocell sensor with ON and OFF states
Figure 5.2: Photocell Sensor Operation. This image demonstrates the photocell's function, showing how it detects light levels to switch the transformer ON or OFF, with a built-in delay to prevent false triggers.

Memory Function:

The transformer is equipped with a memory function that retains the last selected power mode. If the unit operates in a specific mode for 24 hours, it will remember that setting even after a power outage, eliminating the need for frequent readjustment.

Image illustrating the memory function of the GKOLED transformer
Figure 5.3: Memory Function. This image highlights the transformer's ability to recall the last used power mode after 24 hours of operation, even following a power interruption.

Official Product Video:

Video 5.1: GKOLED 120W Low Voltage Transformer Overview. This official video from GKOLED provides a visual demonstration of the transformer's features and basic operation.

6. Maintenance

The GKOLED Low Voltage Transformer is designed for minimal maintenance due to its durable construction and fully encapsulated core. However, regular checks can ensure optimal performance and longevity:

  • Cleaning: Periodically wipe the exterior of the transformer with a damp cloth to remove dirt, dust, or debris. Do not use abrasive cleaners or solvents. Ensure the photocell lens is clean and unobstructed for accurate light sensing.
  • Connections: Annually inspect all wire connections at the output terminals to ensure they remain tight and free from corrosion. Loose connections can lead to poor performance or overheating.
  • Ventilation: Ensure the area around the transformer is clear of obstructions to allow for proper airflow and heat dissipation.
  • Photocell Obstruction: Regularly check that no plants, debris, or other objects are blocking the photocell, as this can interfere with its dusk-to-dawn functionality.

7. Troubleshooting

If you encounter issues with your GKOLED Low Voltage Transformer, refer to the following troubleshooting guide:

ProblemPossible CauseSolution
Lights do not turn on.
  • No power to the transformer.
  • Photocell obstructed or faulty.
  • Incorrect operating mode selected.
  • Overloaded circuit.
  • Loose wire connections.
  • Faulty lighting fixtures.
  • Check if the transformer is plugged into a working GFCI outlet. Reset GFCI if tripped.
  • Ensure photocell is clean and unobstructed. Test in a dark environment.
  • Verify the selected mode (e.g., "O" for Always On, "A" for Dusk-to-Dawn).
  • Reduce the total wattage of connected lights.
  • Check and tighten all wire connections at the terminals.
  • Test individual fixtures to identify faulty ones.
Lights turn on/off erratically.
  • Photocell exposed to intermittent light.
  • Photocell overly sensitive (as noted in some user experiences).
  • Relocate the transformer to an area with consistent light/dark conditions.
  • Ensure the photocell is not receiving light from other sources (e.g., house lights, car headlights).
  • If issues persist, contact GKOLED customer support.
Timer function not working correctly.
  • Incorrect mode selected.
  • Power interruption.
  • Confirm a timed mode (1-9) is selected.
  • Allow the unit to run for 24 hours in the desired mode for the memory function to activate.

If the problem persists after attempting these solutions, please contact GKOLED customer support for further assistance.

8. Specifications

FeatureDetail
Model Number120W (120V-12V)
Nominal Capacity120W
Input Voltage120V AC
Output Voltage12V AC
Output Channels2
Power Modes11 (O, A, 1-9)
PhotocellIntegrated, with 30-second tolerance
Core TypeFully Encapsulated Toroid Core
Housing MaterialHeavy-duty Steel
CertificationsETL Listed, CEC Level VI Certified
Product Dimensions4.9 x 4.1 x 7.3 inches
Item Weight5.63 Pounds
Power SourceCorded Electric
Mounting TypeWall Mount
Dimensions of the GKOLED 120W Low Voltage Transformer
Figure 8.1: Product Dimensions. The transformer measures 7.3 inches in height, 4.7 inches in width, and 4 inches in depth.

9. Warranty and Support

This GKOLED Low Voltage Transformer is covered by a 2-year warranty from the date of original purchase. This warranty covers defects in materials and workmanship under normal use.

For warranty claims, technical support, or any questions regarding your product, please contact GKOLED customer service. Please have your purchase receipt and model number ready when contacting support.

We are committed to providing top-rated customer service and are here to help with any issues you may encounter.

© 2025 GKOLED. All rights reserved.

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