USB Serial Port Control Relay Module Sturdy Durable Lightweight USB Relay Module USB Intelligent Control Switch Overcurrent Protection Intelligent Command Control Switch Intelligent Home

Works instantly and shows up in device manager as a serial COM port CH340. Used this to switch an LED on and Off when a VOIP phone is in use.

Works well, relay sound is pretty loud. Here is a python script I wrote for windows (sound work other systems also) to open/close relay (requires pyserial): #------------------------------------- import serial import sys args = sys.argv print("USB Relay Switch Karlan Mitchell") print("usage: relayswitch.py COM# on/off") ser = serial.Serial(args[1],9600) # open serial port print("Connected on: " + ser.name) # check which port was really used if args[2] == "on": print("Turning on") ser.write(b"\xa0\x01\x01\xa2") elif args[2] == "off": print("Turning off") ser.write(b"\xa0\x01\x00\xa1") else: print("NO ACTION PERFORMED, SEND \"on\" or \"off\"") print("Exiting, bye!") ser.close() #-------------------------------------

Better than advertised. The relay is actually SPDT with connections for common, normally on, and normally off. Some of the Windows drivers are dicey (as in won't work), but a little Googling will find a working driver. On Linux, the driver is a standard part of the kernel, so no additional driver is required. Nifty little gadget, all in all.

These units function as they are supposed to work, until they don't. I purchased a pair of these to do light duty, momentary switching. They were activated infrequently. Both failed within a few days of each other after about 6 months. A simple Python script can control these units.

I've purchased 4-6 of these, after using successfully for 20-40 days or; 2 of the units just stopped working (the 2 broken units are the only that have been plugged in majority of the time). They show up as ttyUSB0 / ttyUSB1 devices in my linux BUT they will no longer receive commands. They worked OK while they worked. Also the build quality is terrible, no way to encase the switch / no screw or mounting holes... The device says upto 250v AC (with no UL Listing), personally i wouldnt put +24v on this thing if its running in my home..

UPDATE: It is "dead Jim..." I can talk to the processor on board, but no more clicky-clicky. I have moved on to the 2 relay and 8-relay board which use better firmware (easier to use in Linux) It works, but the software took awhile to find for Linux, and it does NOT work with "usbrelay" package (different firmware). I bought the 2 relay package also, that is easier to get setup.

Quick delivery product as described

Lasted about a week, Then failed. Tried a second unit just like the first, Also failed. Was not switching a load, just using it to switch the remote engagement input for a power supply. Both times the Relay failed.