1. Product Overview
This package contains 100 pieces of 3mm Bi-Color (Red & Green) LED Diodes with a Common Anode configuration and clear round lenses. Additionally, 200 pieces of 1/4 Watt metal film resistors (100x 430ohm and 100x 470ohm) are included for use with DC 6-12V power supplies.
These LEDs feature low energy consumption and low heat generation, making them suitable for various electronic projects. The diodes have 29mm long leads for convenient operation and soldering.
Image 1.1: Contents of the EDGELEC LED diode and resistor kit.
2. Specifications
- LED Type: 3mm Bi-Color (Red & Green)
- Lens Type: Clear Round Lens
- Configuration: Common Anode
- Lead Length: 29mm
- Red LED Forward Voltage (Vf): DC 2.0V (at If=20mA)
- Green LED Forward Voltage (Vf): DC 3.0V (at If=20mA)
- Forward Current (If): 20mA
- Power Consumption: 0.06 Watts per LED
- Viewing Angle: 30 degrees
- Resistors Included: 100x 430ohm, 100x 470ohm (1/4 Watt Metal Film, ±1% Tolerance)
- Recommended Voltage Range (with included resistors): DC 6-12V
- Operating Life: 50,000 Hours
- Material: Metal
2.1. Detailed LED Parameters
Image 2.1: Detailed electrical parameters for various LED colors, including Red and Green.
The table above provides detailed electrical characteristics for various LED colors, including the Red and Green diodes in this kit. Note the Forward Voltage (Vf), Luminous Intensity (mcd), Wavelength, and Viewing Angle for each color at a Forward Current (If) of 20mA.
2.2. Physical Dimensions
Image 2.2: Technical drawing showing the dimensions of the 3mm LED diode in millimeters.
Refer to the diagram above for precise physical dimensions of the 3mm LED diodes, including lens diameter, lead length, and spacing, all measured in millimeters.
3. Setup and Connection
These bi-color LEDs are Common Anode type, meaning the longest lead (common anode) should be connected to the positive (+) terminal of your power supply, and the other two leads (cathodes for Red and Green) should be connected to the negative (-) terminal through a current-limiting resistor.
3.1. Identifying Leads
- The longest lead is the Common Anode (+).
- The shorter leads are the Cathodes (-) for the Red and Green colors.
Image 3.1: Diagram illustrating the common anode configuration and lead identification for the bi-color LED.
As shown in the diagram, 'C' represents the Common Anode, 'A' is the Cathode for one color (e.g., Red), and 'B' is the Cathode for the other color (e.g., Green).
3.2. Resistor Connection
A current-limiting resistor is essential to protect the LED from excessive current and ensure its longevity. The included 430ohm and 470ohm resistors are suitable for DC 6-12V applications.
Image 3.2: Bags containing the 430ohm and 470ohm metal film resistors included with the LED diodes.
To connect, place a resistor in series with each cathode lead (A and B) before connecting to the negative terminal of the power supply. The common anode lead (C) connects directly to the positive terminal of the power supply.
Calculation for Resistor Value:
R = (Vs - Vf) / If
- R = Resistor value in Ohms
- Vs = Supply Voltage (e.g., 6V, 9V, 12V)
- Vf = Forward Voltage of the LED (Red ≈ 2.0V, Green ≈ 3.0V)
- If = Desired Forward Current (typically 20mA or 0.02A)
Example: For a 12V supply and a Red LED (Vf=2.0V, If=0.02A):
R = (12V - 2.0V) / 0.02A = 10V / 0.02A = 500 Ohms. A 470ohm resistor is a suitable standard value.
Example: For a 12V supply and a Green LED (Vf=3.0V, If=0.02A):
R = (12V - 3.0V) / 0.02A = 9V / 0.02A = 450 Ohms. A 430ohm resistor is a suitable standard value.
4. Operating Instructions
Once properly connected with the appropriate current-limiting resistors, these bi-color LEDs can display either red or green light, or a combination of both, depending on which cathode leads are connected to ground (through resistors).
- To illuminate Red: Connect the common anode to positive, and the Red cathode (through a resistor) to negative.
- To illuminate Green: Connect the common anode to positive, and the Green cathode (through a resistor) to negative.
- To illuminate both Red and Green simultaneously: Connect the common anode to positive, and both the Red and Green cathodes (each through its own resistor) to negative. The resulting color will be a mix of red and green.
Ensure the supply voltage is within the recommended range (6-12V DC when using the included resistors) to prevent damage to the LEDs.
5. Maintenance
These LED diodes are robust electronic components designed for long-term use with minimal maintenance.
- Storage: Store LEDs in a dry environment, away from direct sunlight, high temperatures, and excessive humidity. Keep them in their original packaging or an anti-static bag to prevent damage.
- Cleaning: If necessary, gently clean the LED lens with a soft, dry cloth. Avoid using harsh chemicals or abrasive materials.
- Soldering: When soldering, ensure the soldering iron temperature is appropriate and soldering time is kept to a minimum (less than 3 seconds at 482°F-527°F). Avoid applying excessive mechanical stress to the leads during and after soldering.
6. Troubleshooting
If your LED diode is not functioning as expected, consider the following troubleshooting steps:
- LED Not Lighting Up:
- Verify correct polarity: Ensure the common anode is connected to positive and the cathode(s) to negative (through a resistor).
- Check power supply: Confirm the power supply is providing the correct voltage and is turned on.
- Inspect connections: Ensure all wires are securely connected and there are no loose contacts or short circuits.
- Resistor value: Confirm the correct resistor value is used for your supply voltage. Too high a resistance may result in no light or very dim light. No resistor will likely burn out the LED.
- Damaged LED: Although rare, an LED might be faulty. Test with another LED from the pack.
- Incorrect Color Displayed:
- Ensure the correct cathode lead is connected for the desired color.
- If both colors are lit when only one is desired, check for unintended connections or shorts between the cathode leads.
- Dim Light Output:
- Check the resistor value; a higher resistance will result in lower current and dimmer light.
- Verify the supply voltage is adequate for the LED's forward voltage.
7. Warranty and Support
EDGELEC products are manufactured to high standards. For any issues or technical support, please refer to the seller's return policy or contact EDGELEC customer service through the platform of purchase. Standard return policies typically allow for returns or replacements within 30 days of purchase for defective items.