{"product_id":"2-channel-relay-module-5v-12v-24v-optocoupler-isolated-arduino-ac250v-10a","title":"2-Channel Relay Module 5V \/ 12V \/ 24V | Optocoupler Isolated High\/Low Trigger | AC 250V 10A | Arduino","description":"\u003ch2\u003e2-Channel Relay Module — 5V \/ 12V \/ 24V | Optocoupler Isolated | AC 250V 10A | High\/Low Level Trigger\u003c\/h2\u003e\n\n\u003cp\u003eA versatile, optocoupler-isolated 2-channel relay module that lets any microcontroller — Arduino, ESP32, Raspberry Pi, or STM32 — switch mains AC loads (up to 250V\/10A) and DC loads (up to 30V\/10A) safely and reliably. The critical feature of this module is its \u003cstrong\u003eoptocoupler isolation\u003c\/strong\u003e: the control circuit (your microcontroller) is electrically separated from the relay coil and load circuit, protecting your microcontroller from voltage spikes, inductive kickback, and ground loops that would otherwise damage or reset it. A jumper wire selects high-level or low-level trigger to match your microcontroller’s output logic. Available in 5V, 12V, and 24V coil voltage versions.\u003c\/p\u003e\n\n\u003ch3\u003eSpecifications\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eChannels\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e2 (independent)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCoil Voltage\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5V DC \/ 12V DC \/ 24V DC (as selected)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTrigger Current\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e5mA\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eTrigger Level\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eHigh or Low (jumper selectable)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eIsolation\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eOptocoupler (electrical isolation between control and load)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMax AC Load\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eAC 250V \/ 10A\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eMax DC Load\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eDC 30V \/ 10A\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eModule Dimensions\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003e50 × 41 × 18.5mm\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eIndicators\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eGreen (power) + Red per channel (relay status)\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eOutput Terminals\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eNC, COM, NO per channel (6 screw terminals total)\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eWhy Optocoupler Isolation Matters\u003c\/h3\u003e\n\u003cp\u003eRelay coils are inductive loads — when switched off, they generate a voltage spike (back-EMF) that can be many times the supply voltage. Without isolation, this spike travels back through the control signal line and into your microcontroller’s GPIO pin, causing:\u003c\/p\u003e\n\u003cul\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGPIO pin damage\u003c\/strong\u003e — overvoltage destroys the input protection diodes on the microcontroller pin\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eMicrocontroller reset\u003c\/strong\u003e — voltage spikes on the power rail cause brownout resets\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eData corruption\u003c\/strong\u003e — electrical noise from relay switching corrupts I2C, SPI, and UART communications\u003c\/li\u003e\n  \u003cli\u003e\n\u003cstrong\u003eGround loops\u003c\/strong\u003e — shared ground between high-current relay circuits and sensitive microcontroller circuits causes measurement errors\u003c\/li\u003e\n\u003c\/ul\u003e\n\u003cp\u003eThe optocoupler on this module uses an LED and phototransistor to transmit the control signal as light — completely breaking the electrical connection between the microcontroller and the relay coil. Your microcontroller is fully protected.\u003c\/p\u003e\n\n\u003ch3\u003eHigh vs. Low Level Trigger — How to Choose\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eTrigger Mode\u003c\/th\u003e\n\u003cth\u003eRelay ON when\u003c\/th\u003e\n\u003cth\u003eRelay OFF when\u003c\/th\u003e\n\u003cth\u003eUse with\u003c\/th\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eHigh Level\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eSignal = HIGH (3.3V or 5V)\u003c\/td\u003e\n\u003ctd\u003eSignal = LOW (0V)\u003c\/td\u003e\n\u003ctd\u003eMost Arduino\/ESP32 GPIO outputs\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eLow Level\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eSignal = LOW (0V)\u003c\/td\u003e\n\u003ctd\u003eSignal = HIGH (3.3V or 5V)\u003c\/td\u003e\n\u003ctd\u003eOpen-collector outputs, active-low systems\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\u003cp\u003eSet the trigger level using the jumper wire on the module. No code changes required — just move the jumper.\u003c\/p\u003e\n\n\u003ch3\u003eOutput Terminal Wiring\u003c\/h3\u003e\n\u003ctable\u003e\n  \u003ctbody\u003e\n    \u003ctr\u003e\n\u003cth\u003eTerminal\u003c\/th\u003e\n\u003cth\u003eFunction\u003c\/th\u003e\n\u003cth\u003eConnect To\u003c\/th\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eCOM\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eCommon (always connected)\u003c\/td\u003e\n\u003ctd\u003eOne side of your load or power supply\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eNO\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eNormally Open (open when relay OFF)\u003c\/td\u003e\n\u003ctd\u003eLoad — circuit closes when relay activates\u003c\/td\u003e\n\u003c\/tr\u003e\n    \u003ctr\u003e\n\u003ctd\u003e\u003cstrong\u003eNC\u003c\/strong\u003e\u003c\/td\u003e\n\u003ctd\u003eNormally Closed (closed when relay OFF)\u003c\/td\u003e\n\u003ctd\u003eLoad — circuit opens when relay activates\u003c\/td\u003e\n\u003c\/tr\u003e\n  \u003c\/tbody\u003e\n\u003c\/table\u003e\n\n\u003ch3\u003eKey Features\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eOptocoupler isolation\u003c\/strong\u003e — full electrical separation between microcontroller and relay\/load circuit\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eAC 250V \/ 10A load rating\u003c\/strong\u003e — switches mains lighting, motors, heaters, and appliances\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eDC 30V \/ 10A load rating\u003c\/strong\u003e — switches DC motors, solenoids, and high-current DC loads\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eHigh\/Low trigger selectable\u003c\/strong\u003e — jumper wire selects trigger polarity, no code changes needed\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003e5mA trigger current\u003c\/strong\u003e — compatible with 3.3V and 5V GPIO outputs from Arduino, ESP32, Raspberry Pi\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eLED status indicators\u003c\/strong\u003e — green power LED + red relay status LED per channel for visual feedback\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eNC\/COM\/NO terminals\u003c\/strong\u003e — both normally-open and normally-closed configurations available per channel\u003c\/li\u003e\n  \u003cli\u003e✅ \u003cstrong\u003eCompact 50×41×18.5mm\u003c\/strong\u003e — fits in standard project enclosures\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eCommon Applications\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003eArduino home automation — switching lights, fans, and appliances\u003c\/li\u003e\n  \u003cli\u003eESP32 \/ ESP8266 WiFi-controlled mains switching\u003c\/li\u003e\n  \u003cli\u003eRaspberry Pi GPIO relay control for home automation\u003c\/li\u003e\n  \u003cli\u003eIndustrial PLC output expansion\u003c\/li\u003e\n  \u003cli\u003eGreenhouse and aquarium automation (lights, pumps, heaters)\u003c\/li\u003e\n  \u003cli\u003e3D printer heated bed and hotend power switching\u003c\/li\u003e\n  \u003cli\u003eCNC machine spindle and coolant pump control\u003c\/li\u003e\n  \u003cli\u003eAutomatic irrigation system pump control\u003c\/li\u003e\n\u003c\/ul\u003e\n\n\u003ch3\u003eArduino Wiring Example\u003c\/h3\u003e\n\u003col\u003e\n  \u003cli\u003eConnect module VCC to Arduino 5V (or 12V\/24V external supply for 12V\/24V versions).\u003c\/li\u003e\n  \u003cli\u003eConnect module GND to Arduino GND.\u003c\/li\u003e\n  \u003cli\u003eConnect IN1 to Arduino digital pin (e.g., D7) for channel 1 control.\u003c\/li\u003e\n  \u003cli\u003eConnect IN2 to Arduino digital pin (e.g., D8) for channel 2 control.\u003c\/li\u003e\n  \u003cli\u003eSet jumper to HIGH trigger (default for most Arduino projects).\u003c\/li\u003e\n  \u003cli\u003eWire your AC or DC load between COM and NO (or NC) terminals.\u003c\/li\u003e\n  \u003cli\u003eUse \u003ccode\u003edigitalWrite(7, HIGH)\u003c\/code\u003e to activate relay 1, \u003ccode\u003edigitalWrite(7, LOW)\u003c\/code\u003e to deactivate.\u003c\/li\u003e\n\u003c\/ol\u003e\n\u003cp\u003e\u003cem\u003eWarning: AC mains wiring must be performed by a qualified electrician. Ensure all mains connections are insulated and the module is housed in a suitable enclosure before powering.\u003c\/em\u003e\u003c\/p\u003e\n\n\u003ch3\u003eFrequently Asked Questions\u003c\/h3\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Can I use the 5V module with a 3.3V Arduino (e.g., Arduino Due, ESP32)?\u003c\/strong\u003e\u003cbr\u003eA: Yes. The optocoupler trigger current is only 5mA, which is within the output capability of 3.3V GPIO pins. The relay coil is powered separately from the module VCC — connect VCC to 5V and use 3.3V signals on the IN pins.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: Can I switch both channels simultaneously?\u003c\/strong\u003e\u003cbr\u003eA: Yes. Both channels are independent and can be activated simultaneously or in any sequence.\u003c\/p\u003e\n\u003cp\u003e\u003cstrong\u003eQ: What is the relay switching lifetime?\u003c\/strong\u003e\u003cbr\u003eA: Standard relay modules of this type are rated for approximately 100,000 mechanical switching cycles at rated load. Reduce load current to extend relay life.\u003c\/p\u003e\n\n\u003ch3\u003ePackage Contents\u003c\/h3\u003e\n\u003cul\u003e\n  \u003cli\u003e1× 2-Channel Relay Module (coil voltage as selected: 5V \/ 12V \/ 24V)\u003c\/li\u003e\n\u003c\/ul\u003e","brand":"Keszoox","offers":[{"title":"12V","offer_id":46981894537451,"sku":"14:10#12V","price":5.08,"currency_code":"USD","in_stock":true},{"title":"5V","offer_id":46981894570219,"sku":"14:350852#5V","price":5.08,"currency_code":"USD","in_stock":true},{"title":"24V","offer_id":46981894602987,"sku":"14:200004889#24V","price":5.2,"currency_code":"USD","in_stock":true}],"thumbnail_url":"\/\/cdn.shopify.com\/s\/files\/1\/0677\/1005\/8731\/files\/2-channel-relay-module-5v-12v-24v-optocoupler-arduino.webp?v=1761112773","url":"https:\/\/keszoox.com\/products\/2-channel-relay-module-5v-12v-24v-optocoupler-isolated-arduino-ac250v-10a","provider":"Keszoox","version":"1.0","type":"link"}