Review on 📡 Optocoupler Support Trigger by HiLetgo Channel by Mike Groover

I use this in a small tracked robot chassis as a primitive estop for motors when my power supply sensor detects an overcurrent condition. I'm very conscientious about this project so I took some measurements. It works well with both 3.3V and 5V power supplies. There are DC+ and DC inputs for power and a trigger input for relay activation. The relay has contacts for both normally open and normally closed operation. Active high or active low triggers are selectable with a single jumper. It works as expected. In general, the construction and soldering are reliable. I can't say anything about the durability yet, but I don't see any problems at the moment. Current (relay not activated): 1.43 mA Relay activated: supply 50 mA, trigger current 1.0 mA 3.3 VDC TRIGGER ***** Follow-up 3/29/21 This relay was installed in a factory test bench and has been working for over a year properly with a 3.3V relay and trigger supply voltage. The relay is currently intermittent. The board will fire (you can see and aim the LED) but the relay coil will not fire. I figured I'd have to change the board's power supply to 5V and bingo. It works. It seems that 3.3V is barely enough to power the coil. My guess is that a resistor or something needs to be changed to work properly at 3.3V. The 3.3V trigger is still in use and appears to be working.