2 channel 12V relay module with optocoupler High and Low Level Trigger

SKU: FA2085-0-8
Channels

2 Independent Relays

Control Voltage

12V DC

Trigger Mode

High or Low Level (Jumper Selectable)

Isolation Voltage

2500V RMS

Relay Contact Rating

10A @ 250VAC / 10A @ 30VDC

Relay Type

Electromagnetic, SPDT

Input Current (per channel)

~5-10mA

Dimensions

Approx. 80mm x 55mm x 20mm

Product Description

The 2 Channel 12V Relay Module with Optocoupler is a versatile and professional-grade interface designed for reliable, isolated control in 12V-based systems. This module acts as a secure and intelligent bridge between 12V logic signals from controllers, Programmable Logic Controllers (PLCs), or automotive systems and various high-power AC or DC loads. Its core innovation is the integration of advanced optocouplers for both channels, creating a critical 2500V electrical isolation barrier. This barrier completely separates your sensitive 12V control electronics from the potentially noisy and hazardous high-voltage/current load side, ensuring immunity from damaging voltage spikes, ground loops, and electromagnetic interference.
Engineered for maximum flexibility, the module features selectable high-level or low-level trigger logic for each channel via simple jumpers. This provides seamless compatibility with any 12V control signal type, whether sourcing (PNP) or sinking (NPN). Combining dual high-current relay outputs, clear status indicators, and secure screw terminal connections, this compact module is the ideal solution for applications requiring robust, protected, and flexible dual-circuit switching, from industrial sensors to smart automotive accessories.

Key Features

  • Dual-Channel Opto-Isolation:​ Both independent channels are protected by individual optocouplers, providing 2500Vrms of isolation to shield your 12V controller from load-side electrical noise and transients.
  • Selectable Trigger Logic:​ Each channel can be configured for High-Level (active on +12V) or Low-Level (active on 0V) trigger via a jumper, ensuring compatibility with all 12V control outputs.
  • Industrial 12V DC Compatibility:​ Designed for direct integration into standard 12V control environments common in industrial, automotive, and automation applications.
  • High-Current Relay Outputs:​ Features two robust electromagnetic relays with SPDT contacts, each rated to switch loads up to 10A at 250VAC or 30VDC.
  • Clear Visual Feedback:​ Dual LEDs per channel provide immediate status: one indicates opto-isolator input activation, and the other confirms physical relay switching.
  • Secure & Reliable Connections:​ All high-power load and DC power inputs use reliable screw terminals for safe, vibration-resistant installations.
  • Integrated Voltage Spike Protection:​ Each relay coil includes a flyback diode to suppress inductive kickback, protecting the driving circuitry and ensuring longevity.
  • Compact & Versatile Design:​ A small footprint makes it easy to integrate into control panels, enclosures, or space-constrained projects.

Main Parameters

  • Channels:​ 2 Independent Relays
  • Control Voltage:​ 12V DC
  • Trigger Mode:​ High or Low Level (Jumper Selectable)
  • Isolation Voltage:​ 2500V RMS
  • Relay Contact Rating:​ 10A @ 250VAC / 10A @ 30VDC
  • Relay Type:​ Electromagnetic, SPDT
  • Input Current (per channel):​ ~5-10mA
  • Dimensions:​ Approx. 80mm x 55mm x 20mm

Typical Applications / Usage

  1. Industrial Sensor/Actuator Interface:​ Safely connect a 12V PLC to control two independent actuators, solenoid valves, or indicator lights.
  2. Automotive Accessory Control:​ Manage two high-power accessories (e.g., a light bar and a winch) from a 12V switch or vehicle computer with complete noise isolation.
  3. Basic HVAC Control:​ Control a fan and a heater in a small environmental control or ventilation system using a 12V thermostat or timer.
  4. Security & Alarm Systems:​ Activate two separate alarms, sirens, or strobe lights based on 12V sensor inputs, with protection for the control panel.
  5. Prototyping & Testing:​ A reliable, isolated output module for engineers developing and testing 12V-controlled products or systems.
  6. Agricultural Controls:​ Automate two devices, such as a water pump and a ventilation fan, in a small greenhouse or irrigation setup.
Connection & Configuration Guide:
  1. Trigger Configuration:​ For each channel, place the jumper cap over the pins labeled “H”​ (High-Level trigger) or “L”​ (Low-Level trigger) to match your controller’s output logic.
  2. Power & Control Wiring:​ Connect a stable 12V DC power supply to the module’s VCC​ and GND​ terminals. Connect the two signal input pins (IN1, IN2) to the digital outputs of your 12V controller.
  3. Load Wiring:​ For each channel, connect the device’s power source to the relay’s COM​ terminal. Connect the device to the NO​ terminal to be powered when the relay activates.
  4. Critical Safety:Always disconnect all high-voltage power before wiring.​ Install the module in a proper insulated enclosure and follow all electrical safety codes.
Q: Why do I need an optocoupler on a 12V relay module?

The optocoupler provides electrical isolation, preventing noise, voltage spikes, and ground loops from the load circuit (e.g., a motor) from damaging or interfering with your sensitive 12V controller. This is crucial for reliability in noisy environments like vehicles or factories.

Q: My controller outputs 24V. Can I use this 12V module?

No, not directly.​ Applying 24V to the inputs or VCC will damage the module. You need a 24V-specific module or a voltage regulator to step down to 12V.

Q: Should I use High or Low-Level trigger?
  • High-Level:​ Use if your controller outputs +12V to activate (common for PLC “sourcing” outputs).
  • Low-Level:​ Use if your controller connects to ground (0V) to activate (common for “sinking” outputs).
    Check your controller’s manual.
Q: What 12V power supply do I need?

You need a stable 12V DC supply. Each relay coil draws about 80-100mA when on. For both relays active, ensure your supply can provide at least 200mA continuously.

Q: Can I control a 3-phase motor with this?

No, not directly.​ This module uses single-pole relays. Control a 3-phase motor by using one channel to activate the coil of a 3-pole contactor, which switches the motor.

Q: The opto LED is on but the relay doesn't click. Why?

This usually means the relay coil is not getting power. Check that your 12V power supply connected to VCC​ is working and provides enough current. The opto-isolator and relay coil are on separate circuits.

Q: Can I switch AC and DC loads on the two channels?

Yes.​ The relay contacts are rated for both. You can have 120VAC on one channel and 24VDC on the other, as they are completely independent.

Q: Is this suitable for business or OEM use?

Yes.​ Its professional specs make it suitable for integration into commercial products, control panels, and OEM equipment. We offer volume pricing for business clients. Contact our sales team for details.