Review on 🔌 SunFounder 5V 8 Channel Relay Shield Module: Compatible with Arduino R3, Raspberry Pi 3, 2 Model B & B+ by James Wickware

works with my fake Arduino. Looks solid, both relays work fine. The clamps hold the 14ga single wire super tight, but probably can't open and close them much more without stripping some insulation. When the input goes low (<0.6V), the relay turns on and the LED lights up. This was counterintuitive at first, and requires your controller to signal "high" for the entire time you want the device to turn off. So for a lamp that turns on 15 minutes a day, I'm providing a "high" 5V signal for 23.25 hours. If my controller fails, the signal goes low and all the relays are activated. Lights, heaters, motors, etc. are turned on when the system fails. For security reasons I would prefer a device that wakes up when the Arduino sends a signal and throws an error when there is no signal.