There is an updated version of this product available: KIT-13815
Description: Your 5 volt system can wield great power with this big beefy relay board. How does 20 amps at 220VAC sound? The SparkFun Beefcake Relay Control Kit contains all the parts you need to get your high-power load under control.
The heart of the board is a sealed, SPDT-NO 20A Relay. The relay is controlled by 5V logic through a transistor and an LED tells you when the relay is closed. This is a kit, so it comes as through-hole parts with assembly required which makes for some nice soldering practice. Screw terminal connectors on either side of the board make it easy to incorporate into your project.
Note: There are some pretty beefy traces connecting the relay to the load pins, but the 2-pin terminals are only rated for 8A max! If you plan on connecting a larger load you’ll need to solder directly to the board. As always with high current and voltage, play it safe and use your judgment when deciding how much of a load you want to put on a board.
Note: Although we have revised this PCB to provide better isolation for the high voltage traces, this board is really meant for someone with some experience. If you’re uncomfortable soldering or dealing with high voltage, please checkout the PowerSwitch Tail II. The PowerSwitch Tail II is fully enclosed making it a lot safer.
Based on 16 ratings:
4 of 4 found this helpful:
I hope that Sparkfun designs this properly in the next revision. Observe clearance distances. Put on a decent terminal block. Use thicker copper. Orient the relay 180 degrees. Use a better impulse snubbing circuit than the current diode. And use a better relay part. And make sure it works well on 3.3v signal voltage.
The good of this is that it is simple. But there are so many design issues with this board, and the relay, at least the one I had, didn’t last long - my application was to control an RV thermostat (12V, electronic load, 150MA) - I needed isolation between the power supply of the RV and the power supply for my micro for other reasons, and thought this looked simple. It failed after maybe 60 days of use (probably 20-50 relay operations a day). I can hear it click when it is signaled to open/close, but I have to “thump” it to make it do something. I’ve since replaced this with a cheap DC SSR (which I basically use like a big optoisolator) and my life is better again - but relays are great because, unlike the SSR, they have little voltage drop and don’t need the cooling at higher amperages that the SSRs do. So this product fills a need, but is just badly designed. Sparkfun, show the future electronics students how to do this right in the next design!
Also, this should use a diffused LED, not the clear non-diffused one it comes with. The only time you should ever use a non-diffused LED is when you have some sort of diffuser in front of it, which is obviously not the common case here. Sure, that’s an easy change if you have a reasonable parts drawer, but not everyone does.
If you aren’t controlling anything critical and just want to switch moderate currents with an Arduino or something for experimentation or fun, this is a great product - I’d just recommend avoiding hooking it to line voltage. It’s a toy and should be treated that way until Sparkfun redesigns it a bit.
1 of 1 found this helpful:
Admittedly, I haven’t soldered much since college, but this was fun to build. One star for fun. Minus one star for having to build the kit, I’d have paid an extra dollar or two to have it built for me.
I bought two kits, and one of them was missing the 10k-ohm resister and instead had three 1k’s in the package (verified under a very strong magnifying glass and lots of lightning). I have plenty of resistors, but by sheer luck I had a 10k resistor small enough to fit on this board.
After assembly, one kit works perfectly (one more star), the other … not so much. The relay clicks when I send a high signal, but there’s no connectivity on the load side of the relay and the LED doesn’t light up. I tested several points on the bottom of the circuit and compared it against the working kit I’d assembled, but no love.
So, one package had a bad resistor, the other had a bad relay… kinda defeats the purpose. Minus two stars since I didn’t really have a way to test this before assembly.
I needed one of these for a hackathon that Intel put on in Denver recently, and it’s a good thing I bought two since one had a bad relay.
Next time I want to spend this much on a relay, I’ll spend the extra two dollars and buy the $9.90 pre-assembled Grove SPDT.
As an aside, big props to the support team at SparkFun trying to track down the package. It was marked “delivered” by USPS on a Friday but wasn’t actually delivered until the following Tuesday or Wednesday. SparkFun was willing to replace the parts for free thinking the package had been lost – they even got on the phone with USPS to find out what had happened.
4 of 4 found this helpful:
I really like this little guy. It works well for most of my needs. However, I’d much prefer it also expose the NC contact. For one of my applications where I need to default to ON, I need to cut the load tracing and add a wire to the NC contact. Nearly every other “similar” offering exposes both contacts. It’s just odd this one does not. That being said, this works better for me than any other I’ve tried at this price point.
I’ll pass your comment along for future consideration if we revise this product. Thanks!
2 of 3 found this helpful:
The quality of these relays are fantastic, I trust them much more than the alternatives you can find online from Chinese distributors. However, even for a person somewhat experienced at soldering it can pose a real challenge due to the size of the pins from the relay.
This would be best sold as a preassembled unit to assure proper connections when dealing with such high voltages/amperages.
The board layout and silkscreening is excellent. Assembly went without any issues. Initial testing of the board seems to indicate that all is well as far as operation is concerned, but I have not had the opportunity to utilize it in the real world yet. I think that the only limiting factor might be is to insure that the load does not exceed the capacity of the relay. I bought two, and would not hesitate to purchase this product again.
It would be nice if it came with a terminal with a higher current rating, say 15-20A.
Easy to use with Arduino or any other 5V microcontroller. Does exactly what it should do. Easy kit to solder – not much to it.
I swapped out the included LED for one with a diffuse lens, which makes it easier to see.
I also soldered the diode directly across the relay coil for better snubbing (lower noise injected back into the power supply), but that is not necessary.
“Click.” If you know which end of a soldering iron to hold on to and can tell orange from brown, this is a simple way of getting your microcontroller to switch high voltages and/or currents.
Suggestion to SFE: Next rev, why not simplify the BOM and use the same connector type as the LV/LC side? That way the HV/HC side can be set up as NC-COM-NO and satisfy people who want connected devices to default to “powered” (Or if they want one device to be on when the other is off.)
I was curious if this kit could be used in a project I have been working on, so I bought one to evaluate. Absent any specific instructions, I carefully studied the silkscreen and product photographs to determine the placement of the resistors and diode.
I am relatively novice when it come to soldering, but starting with the shortest components, I worked my way up to soldering the relay with no problems in about ½ an hour after opening the kit.
A simple test sketch indicates the relay is working fine. I learned a few things from this kit and would recommend it to others.
This was thought out very well. It was easy to solder and get up and running. I really like the LED that indicates when the switch is closed, so you can do testing without have a load attached.
I’ve used a number of these for Electric Imp based control needs and they’ve worked flawlessly. I hope these continue to be offered so I don’t have to find an alternative.
The device was put together with ease and worked as expected. These will be used on my CNC machine that I am building from the ground up.
I purchase about 15 of these over the year and each one has worked perfectly. Using them to control lamps and rope lights and other AC devices. Very easy to interface with other circuits Thank you for a great product. Will purchase some more in the future.
I have ordered 2 of these. One is for a refrigerator that freezes everything and the other is for my new keezer (kegarator) project. Both are currently being controled by Pro Trinket’s from Adafruit. The kits are working fine as far as I can tell. My only issue is the direct soldering of the electrical wire to the board takes quite a bit of heat due to the large traces. Other than not being pretty after that, things are fine though.
The kit has everything you need to make your own Relay Control. Very easy to build and works just as advertised.
The board seems to work well. It was relatively easy to put together. The only issue I had was that none of the LEDs in the four kits I purchased worked, even by themselves in a breadboard. I ended up using my own LEDs which seemed to work just fine… maybe a bad batch?