16-Channel 12V Relay Module Board for Arduino DSP AVR PIC ARM

Ok, I admit it, it took me way too long to figure out how to hook this thing up. In case anyone else is looking at this and wondering how it works, here's how it gets hooked up: 1) The header pins on the bottom of the main picture get wired directly to the Arduino board. Connect one of the 5v pins to a 5v header on your Arduino and connect one of the Gnd pins to a ground header on the Arduino. Each one of the relays has a corrosponding header down there, too, which get connected to a digital output on your Arduino. You can run each wire individually or run over a ribbon cable to a project board and break it out from there. Either way, getting the header pins hooked up allows the logic to fire, and makes the lights work so you can at least diagnose/debug your program. 2) Next, the relay board needs a 12v dc input wired up to the blue terminals on the bottom. These are wired to the relays, which make the relays actually fire. The voltage magnetically pulls a piece of metal away from one pole to the other. This action makes a noticeable clicking noise, which is a little annoying, but also lets you know it's working. 3) Each relay has 3 terminals located along the sides. One side is normally opened, the other is normally closed. Use this to either make or break the circuit that you have wired up for your lights, motors, or whatever else is involved in your project that draws more than 5v or needs to be kept isolated from the Arduino board. So yeah, keep in mind that you'll need a 12v power source to actually make the relays fire. All in all, it's a very well put together board, and would make a great control hub for something like say... a model train set or robot.

The Sainsmart 16 Relay board is an inexpensive bargain. The primary purpose is to isolate the computer from the outputs. RFI or spikes can travel down a wire into a computer and mess up the logic causing any output to go on randomly. This board provides isolation in the relays, the standard usually being 1500 volts and opto isolation on the inputs using an optoisolator diode and optical transistor driving an amplifier. The board is wired when the ground is connected between the computer and the relay board. This is the only power connection needed along with the 16 discreet inputs which operate the relay with a ground input to one of the 16 pins on the header of the board. The 5volt pins 19 and 20 are sufficient to provide power for the computer but the real purpose is to provide input power to run the opto-isolators. Apparently this board has been provided with either 5volt or 12 volt relays. You should check the relay marking before connecting power on the power input pins. The Relays are SPST non-connected contact types, so you may wire virtually any load, but beware that the PC board and the associated connectors will probably not really handle much more than an amp at up to 120vac or 36vdc even though the relay is rated at a higher loads for its contacts. A good input source is Elegoo Mega pins 22 to 55 or a string of 74HC595 serial shift registers. If you connect two relay boards, you will probably need to breakout the wires to prevent connecting a solid 5vdc source to an input pin on the Mega. Note that the Mega has a female socket and the relay board has a male socket. Twenty wire Multicolor flat cable with connectors is a good choice for wiring. Also note that the inputs support open collector inputs which permit wired "OR" wiring. Personally, I would not use the 5vdc pins for anything other than the relay board. For safety operation I would provide +12Vdc at about 0.8Amps or more. I use this board to power 16 slow motion Tortoise switch machines on my Model Railroad using a +12vdc and a +24vdc power source. You really don't need a schematic since the relay board is so redundant in its wiring. The 5 volt converter is a LM2576 12v to 5v 3 amp converter.

I just ordered six more of these boards via Amazon Prime. They are an incredible bargain, and available for even less on eBay if you don't mind waiting a few weeks for shipping from China. Because of previous reviews, I examined these carefully and tested every one right away. All of mine had clean, excellent build quality, and every one worked perfect out of the starting gate. Many electronic products that come out of China are of poor quality, such as some of the Arduino clones, but this Sainsmart product is very high quality. There is a lengthy review of this module by Darrell Thayer, which provides a lot of measurements on current etc. I tested all of these values with my Fluke 177 and all of Darryll's numbers are spot on. I'm using these relay modules, along with an Arduino microcontroller and "Centipede" shift register board, to control turnout solenoids, accessories, and other devices on my model railroad. Incidentally, it doesn't say if these are rated for continuous duty or not. I powered all 16 of the relays and left them energized for a few hours, and while the relay housings were a bit warm to the touch, there was no sign that they were burning up. None of the chips were warm to the touch.

Very impressed for the price. 16 mechanical relays, easily driven from any 5v microcontroller. It may seem slightly annoying to have to power it with a 12v supply, but at least it provides power to the microcontroller controlling it. It also doesn't come with the box, despite the box being shown in the product photo. I could see this being very disappointing to people who... collect... relay board packaging? My point is, you get a board in a antistatic bag in a bigger bubble wrap bag, the board switches lots of electricity and is controlled by any 5v device, and it's cheap. If you need to have a 5v device switch up to 16 large loads using a board that comes in an antistatic bag but not a retail box, and you don't have a huge budget, get this board.

８個のアクチュエーター（DCモーター、電磁弁）のリレー制御に使っています。制御電圧は１２V、マイコンはArduinoMEGAを使っています。スイッチサイエンスのホームページから仕様を読んで、配線方法の確認は必要ですが、初心者でなければ簡単に配線もできると思います。 コストも低価で助かります。注意点としては、リレーが１６個もあるので、やや重くなっています。また、スイッチの動作は、アクティブLOWなので、始めのプログラミングの際に間違えやすいかもです。

Awesome product. Perfect solder joints. No residual flux. No bridges. Can't beat it for the price. Will recommend to friends and will buy again!

箱はありませんできたが、緩衝材と静電袋に梱包されて届きました。動作も問題ありませんでした。

動作的にはまったく問題ないのですが、リレー接点の端子に注意。 基板上にはA接点風の記号しか書かれておらず、参考になりません。 端子を手前、リレーを奥に見て、向かって左からNO、COM、NCとなります。 事前にテスターで調べてから配線することをおすすめします。