12V 8-Channel Relay Module with Optocoupler – Support Documentation
The 12V 8-Channel Relay Module with Optocoupler is designed to control multiple high-voltage devices using low-voltage signals from microcontrollers like Arduino, Raspberry Pi, and ESP32. Featuring optocoupler isolation, it ensures protection for your control systems against voltage spikes and electrical noise.
Specifications
| Parameter | Details |
|---|---|
| Operating Voltage | 12V DC |
| Number of Channels | 8 |
| Relay Type | SPDT (Single Pole Double Throw) |
| Trigger Voltage | 3.3V – 5V |
| Trigger Current | 5mA |
| Max Switching Voltage (AC) | 250V @ 10A |
| Max Switching Voltage (DC) | 30V @ 10A |
| Optocoupler Isolation | Yes |
| Trigger Mode | Configurable: High or Low Level |
| Dimensions | 138mm x 57mm x 17mm |
| Mounting Holes | 4 holes, 3.1mm diameter |
Pinout Description
| Pin | Description |
|---|---|
| DC+ | 12V positive power supply |
| DC- | Ground connection |
| IN1 – IN8 | Control signal inputs for channels 1 to 8 |
| COM1 – COM8 | Common terminals for each relay |
| NO1 – NO8 | Normally Open terminals for each relay |
| NC1 – NC8 | Normally Closed terminals for each relay |
Features
- Optocoupler isolation for each channel to protect microcontrollers from voltage spikes.
- Configurable trigger modes (High or Low level) via jumpers for compatibility with various control signals.
- LED indicators for power status and relay activation status.
- High-quality screw terminals for secure and easy wiring.
- Suitable for controlling both AC and DC loads such as lights, motors, and solenoids.
Wiring and Setup
- Power Supply: Connect the 12V DC power supply to the DC+ and DC- terminals.
- Control Signals: Connect the control signal pins (IN1 to IN8) to the digital output pins of your microcontroller.
- Load Connections: Connect your load devices to the NO (Normally Open), NC (Normally Closed), and COM (Common) terminals as per your requirement.
- Trigger Mode Configuration: Set the jumpers to select High or Low-level triggering based on your microcontroller’s logic levels.
Trigger Mode Configuration
| Jumper Setting | Trigger Mode | Description |
|---|---|---|
| H | High-Level Trigger | Relay activates when control signal is HIGH |
| L | Low-Level Trigger | Relay activates when control signal is LOW |
Troubleshooting
- Relay Not Activating: Ensure that the control signal voltage matches the trigger mode configuration. Check power supply connections.
- LED Indicators Not Lighting: Verify that the 12V power supply is connected properly and supplying the correct voltage.
- Unresponsive Channels: Test each channel individually to isolate the issue. Check for faulty relays or poor solder joints.
- Microcontroller Resetting: Ensure that the power supply can handle the current draw of all activated relays. Consider using a separate power supply for the relay module.
Frequently Asked Questions (FAQs)
- Q: Can I use this relay module with a 5V microcontroller?
- A: Yes, the module can be triggered with 3.3V to 5V signals. Ensure that the trigger mode is set appropriately.
- Q: What is the purpose of the optocoupler in this module?
- A: The optocoupler provides electrical isolation between the control circuit (microcontroller) and the relay circuit, protecting sensitive components from voltage spikes.
- Q: How do I choose between the NO and NC terminals?
- A: Use the Normally Open (NO) terminal if you want the circuit to be closed (powered) only when the relay is activated. Use the Normally Closed (NC) terminal if you want the circuit to be closed when the relay is not activated.
- Q: Can I control AC and DC loads with this module?
- A: Yes, the relay module can control both AC (up to 250V) and DC (up to 30V) loads, each up to 10A.
Safety Precautions
- Always disconnect power before wiring the module to prevent electric shock.
- Ensure that the connected loads do not exceed the relay’s maximum voltage and current ratings.
- Use proper insulation and secure connections to prevent short circuits.
- When switching AC loads, ensure compliance with local electrical regulations and standards.
Applications
- Home automation systems
- Industrial control systems
- Robotics
- Remote control of appliances
- Automated testing equipment
For further assistance or inquiries, please contact our support team.