2PCS 4 Channel 5V Relay Module with Optocoupler High or Low Level Trigger Expansion Board for Raspberry Pi Arduino

Update: I'm dumb. Not the manufacture or Amazons fault, for the failures. I made a miscalculation and was able to fix it. Even the company reached out to see what was wrong!!!Pre purchased these for a project that took a year and a half to finish. I am finally finishing up just to come to find out none of them work even with direct current to the coil leads. Out $15 and have to order something different. Will update as needed. At current time stay away from the single pack ones.

I use these on a Tram that goes up and down a steep slope.The relay board on the winch end is for up, down, fast and slow speed control.The relay board on the tram end is for steering via a linear actuator and for leveling the tram via another set of linear actuators.These relays are activated by arduino boards and activate larger high current relays. They are also easy to troubleshoot because each relay on the board has an led that lights up when relay is active.I have been using these for a year with no problems and considering the low price are a great investment.

Reliably switching 24v sprinkler solenoid valves for over a year. Good price! Got a backup... It's in an outdoor enclosure so I don't care about the noise (yes, it's a mechanical relay) or the LED (nice visual feedback). Easy to integrate with an Arduino and I think it'll do just fine. The system doesn’t stay out in the winter but it's there during the 100°+ heat. I have not experienced any negative issues with the Arduino and I assume it's optically isolated to the controller/signal.

I have 10 of these single relay 12vdc modules (so far). I use them for MANY applications.In one application, I am powering it from 11.5vdc from a small buck regulator to keep voltage stable.I am triggering from 11.5vdc through a 68k resistor so, = (about)1.6vdc gives me a high trigger. _|-|_For solar applications, I have pulled the relay off and used solid state relay! Easy Peasey!I have also used it to switch my 3000watt power inverter off and on with no relay at all.Yes, I pulled the relay, lifted pins 3 and 4 of the opto coupler out of the board, soldered wires to them. Inserted wires to COMMON and N.O. pads on the PCB!The inverter just needs a small make/break, positive action switch to control its power on / power off logic from its' wired factory remote.The opto couplers output does this perfectly and no relay sucking power.So, a combination of a programmable comparator and this great little board, I have and ATS (automatic transfer switch) controller for my solar which uses FAR LESS energy (and money) than any commercial unit out there. And it turns the inverter off and on! AND a fully programmable solution to meet my LiFePO4's requirements.There are no mechanical relays pulling ~100ma each on either board!When using solar, draining around a quarter amp at 12-13.6 vdc for 12 hours is a lot of waste.So, these little wonders can be used to drive pretty much anything!1- Stock relay works.2- Pull the stock relay and replace with solid state.3- Pull the stock relay out and lift pins 3 & 4 of opto coupler off the board and you can control logic with said pins!Triggers off of very low voltage too!My only CON is the wire capture strips. Really too small and rinky dink.

Works great with Raspberry Pi running HomeAssistant

I've bought 4 of these, only because it's my only option without waiting 30-40 days for a better product direct from Asia.The 1st was DOA (1 or more channels did not work at all).The 2nd worked initially, but because I slightly "overtightened" (wasn't really too tight) the DC+ input terminal, the connection from that terminal to the board became loose and the unit would not reliably stay on. These things are made SOOOO cheaply!!!The 3rd and 4th were DOA (each had a different channel non-functional). I ordered 2 even though I just needed one, because I needed to work on it this weekend and knew my chances of getting a bad one were high. Guess I should have ordered 10 and hoped for 10% success rate?So now I'm waiting on replacements for the last couple of DOA units. And even if they work, I'll be forever worried that something is going to break and I'll have to take my entire project apart to replace the relay. What are the odds something like this will last 10 years or even 1 year, given how incredibly poorly it is made the the unbelievably high failure rate?I would gladly pay more for something that just works, but this seems to be the only option other than waiting a month or more. (And I will be ordering a couple of those to have on hand, but for now I can't wait that long to use them.)

I recently changed all my lights to ZWave to reduce the WiFi pollution in my home. I needed a ZWave module to use as a trigger for an automation when my Vista20P alarm is tripped but found that no one makes a ZWave module that can be wired directly to my Honeywell Vista20P alarm system. I was able to use this relay module between the alarm and the zwave module. It works great and has been very reliable. Now when my alarm system is tripped all my lights are turned ON.

The media could not be loaded. one ⭐ review: wrote a basic HIGH LOW program to cycle through relays all relay function except the damaged one.up date Feb 3, 2023 2:12 AM:contacted ANMBEST about damaged relay they responded promptly and resolved the problem with a refund.updating to ⭐⭐⭐⭐⭐ for customer service.