Review on 🔌 SunFounder 2 Channel DC 5V Relay Module with Optocoupler for Arduino R3 MEGA 2560 1280 DSP ARM PIC AVR STM32 Raspberry Pi: Expand and Trigger with Low Level Control by Mark Morrow

This module is perfect! It is soldered and has screw terminals. Like almost all relays of this type, it cannot handle more than 10 A. In the rest of the world this will not be a problem since 230 V circuit breakers work with 10 A. However, in North America with 15A and 20A circuits, this will not work. This limits you to devices with 1200W or less. My first project with him was a plant watering system. The pump only requires 4-12 volts and probably a few hundred milliamps. BTW if you want to power incandescent bulbs or for many other applications I recommend using constant voltage. Incandescent bulbs glow the same way, but it's a lot less dangerous than dealing with AC power. ONE PROBLEM: Relay terminal markers are missing. NO Normally Open, C Common, NC Normally Closed are not printed. A BIG ADVANTAGE: This module is great compared to others because you supply it with 5V from a separate pin, so you don't have to supply the required input current. Pen. The module does that for you. Many boards only have one input pin that you can't use directly, you'll need to build the missing circuitry so you can control the relay with an Arduino or something. Also, very important diodes are missing on some boards! It also has a status LED per relay so you always know what's going on. Note that this is active low.