Review on 🌐 MCIGICM 2 Channel DC 5V Relay Module: Optocoupler Low Level Trigger Expansion Board for Arduino UNO R3, DSP, ARM, PIC, AVR, STM32, Raspberry Pi by Christopher Clearfield

The media could not be loaded. All three boards have at least one faulty relay that continues to work until I physically tap on it to keep it from popping out. Two relays are defective on one circuit board (see video) and one relay is defective on each of the other two circuit boards. I have not yet contacted the seller for a replacement but I will. I supply circuit boards and inputs with 3.3 V. Relays are plugged in both with and without outputs. I haven't used them to drive anything over 3.3V so there shouldn't be any over current or spark issues. I've heard of this problem with high current loads, but it occurs with little or no load. If I'm doing something wrong that's causing this, please let me know so I can edit this review. There was also an issue where the board would trigger the relay when powered up, and actuating the IN1 and IN2 pins would open them again. Will investigate and try to find a solution. If I use it to control the garage door as is, it will open the gate when it loses power and regains power. Other relays I've used don't have this problem. The only good thing I can say about this product is that the build quality (apart from bad relays) seems to be good.