Retired!

This is a retired product, but fear not as there is a newer, better version available: KIT-11042

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Retired RETIRED

This product has been retired from our catalog and is no longer for sale.

This page is made available for those looking for datasheets and the simply curious. Please refer to the description to see if a replacement part is available.

Replacement: KIT-11042. The new board is routed to provide more isolation for the high voltage traces. This page is for reference only.

Description: Your 5 volt system can wield great power with this big beefy relay board. How does 20 amps at 220VAC sound? The 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, SPST-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 unfortunate flaws with this design. If you have this board, we recommend not using it unless you are fully aware of its limitations and problems. There is a small risk that in certain situations this board could become electrically compromised. If this were to happen, the isolation of voltage may become unreliable. To avoid issues, we recommend that you do not use metal hardware to mount this board. Also we recommend that you do not over tighten any hardware to avoid any unneeded damage.  If you would like to return the device for a refund, we would be happy to help you out. We can supply a return label, and a refund, just contact Tech Support, or Customer Service with your order number for assistance with a return.

Documents:

Comments 27 comments

  • As mentioned, DO NOT use the mouting hole in the corner by the “normally open” label. There is no clearance between the screw head or thread and the copper pour. At best, you will blow your fuse if your case is grounded. At worst, it could cause a fire or shock.

    I would not use this above 52v until the spacing issues are fixed.

    • I made a revision of this board today. You can find the revised version here.

      It is still not capable of handling the 20A the relay is capable of, but the isolation between the high and low voltage sections is greatly improved.

      Note that my revision might not be perfect. If anyone has advice for me concerning the board or the routing in general, feel free to let me know.

      • Looks like a better layout to me (although a bit longer), follwing blacklabs suggestions makes for much better spacing on the traces. This video shows what ones of these can do when laid out well!

    • +1 to lowering the voltage rating on this product for safety reasons.

      It’s not easy to use 220VAC at 20 amps with a relay of this type due to PCB limitations. You have to choose a design that’s either high current at low voltage or low current at high voltage. So the PCB can’t be fixed to work safely at both high voltage and high current.

      For high voltages at high currents, consider using a relay with faston type connectors instead.

      • As much as I love sparkfun, its comments like these (and @salsa.. i.e. people who sound like they know what they are talking about), that makes me worried that a site selling to hobbyists is actually run by those who are not much more than hobbyists themselves.

        • Unfortunately I have to agree with most of the comments here THIS PRODUCT IS DANGEROUS AND IS NOT SUITABLE FOR CONNECTION TO MAINS POWER! I’ve worked around the world on big Industrial Power Electronics for many years and am qualified to do so, so think I’m qualified to comment on this. As n1ist pointed out, there is no clearance between the mounting screw and the copper pour and so the risk of shock is very very real. The low voltage traces don’t have nearly enough clearance from the high voltage side. The terminals should have been ones that were rated suitably, rather than just suggesting that they be soldered - many hobbyists would not be able to judge if their soldering was up to the standard needed for 220V wiring. As RSP pointed out, the Faston type relay would have been a better choice.

          This product should be removed from sale right now, before somebody gets hurt.

          • THIS PRODUCT IS DANGEROUS AND IS NOT SUITABLE FOR CONNECTION TO MAINS POWER!

            I agree, those traces are DANGEROUS! I have almost blown up a homemade power supply by putting the mains wires to close.

            • I agree this board needs to be reworked!

              First and Foremost Sparkfun products need to be safe.

              Yes, I agree it takes the end user responsibility to make sure that they use all the products safely. But, I have to agree this one really needs to be redesigned!

              Sparkfun really needs to keep the ‘low’ voltage on one side of the board (Bottom side of the relay in this case) and ‘high’ voltage on the other side (Top side of the relay in this case). This breakout board does not meet that safety.

              I agree that from getting the most ‘Relay Breakout Boards’ per copper clad sheet, this works. But for safety I would make sure the High Voltage Blue Screw Terminals would be on top of the TEE of the relay. There is plenty of space for the LED and it’s resistor, the bypass diode, and the control transistor on the sides of the bottom of the relay.

              I bet if you put this pass UL in its current form, this would never fly.

              If I was to believe one of the old Electrical/Test Engineers I knew, they used to use an old Neon Light Transformers to check traces to make sure everything was far apart enough for their High Voltage runs. I bet this would show the short comings of this design with letting out of great quantities of blue smoke, and other fun sounds. If you try this at home: First, You assume all liabilities if you try this. And Second, please make sure you use the proper eye protection- arc welder mask- because of both what can go flying and because of the flash can damage your eyes.

              The other thing I would do would use the 3-Pin Screw Terminals instead of the 2-Pin Screw Terminal for the High Voltage connection.

              REASON: I would use the outer sides of the 3-pins to prevent the possibility of arcing between any of the traces. And I would make sure the pad around those traces would be as large as you could make them without getting into possible arc conflict. That way you could solder wires if you didn’t use a 3-pin screw terminal.

  • I’m currently in the process of designing a “smart outlet” relay-controlled board, so I’ve done a LOT of research lately, and this product scares the hell out of me. Those traces are WAY too close together. That looks like minimum spacing! I like how the pours are on both sides of the PCB, but having the 5v line run through the top pour? Make them smaller, de-rate the board a bit, and maybe add some small vias in the pours for some thermal dissipation?

    Come on guys, this doesn’t put safety first.

    • Got any more details on your smart outlet project? I have been wanting something similar

      • Give it a few weeks. When Christmas and exams settle down, I’ll put the files up and give away the extra PCBs.

        The plan is to have an open source relay box (v1) with current sensing (v2) for < $10/channel.

  • Also one of the mounting posts in on the load side. This should be isolated. There is a danger of arcing to the lov voltage side, and also if using metal mounting posts, high voltage to the mounting hardware, or worse….. Ouch…

    • Yeah, this circuit seems to be doing absolutely everything I’ve read NOT to do with a power relay circuit. SFE, can you check this and revise?

  • Relay circuits should have switched power leads isolated from the coil switching circuit. This circuit has the coil’s positive lead going right through one of the switched power traces.

  • The revisions of this board need to be reviewed by a safety engineer.

    It is really hard even for professionals to get a PCB design with a relay to deliver 8Amps or the hyperbolic claim of 20Amps. For example, I have had to fix this 3 times on my Bosch dishwasher controller. It is so bad service people carry a spare controller in their trucks. Part of the problem is that the solder fails at these currents.

    Most high current connections are more reliably made by other means e.g. lug connections directly to the relay.

    • I notified Sparkfun about a week or so ago of the safety issues and suggested it should be pulled from sale and recalled straight away and should advise anybody who has already bought it. They reacted quickly and have made stock zero now, though I’m a little disappointed they haven’t put up a notice here about it. I hope they have contacted the people who bought it, but if anybody has bought this, please let us know if Sparkfun have contacted you, as there could be plenty of people that have bought these and are unaware of the dangers.

      @ AdrianFreed - In regards to PCB designs carrying more than 8A, I can assure you that there are plenty of industrial systems out there with connections way over 8A continuous, some around 40A or more, but they use suitable connectors and typically use at least two oz copper on both sides. Soldering is not usually a problem in these instances if it’s done professionally on a good board design, but it’s quite possible (or even likely) that a hobbyist would not be able to gauge whether the joint was good enough or not and that’s part of the danger here. So, yes lugs would be far more suited to this application, though again they have to be properly crimped. Sounds like you’ve had some fun with your dishwasher boards though!

      • I bought the bare PCB that is included in this kit. I have not heard anything from sparkfun.

  • I don’t think I would connect a microcontroller directly to this board. An opto-isolator would be an improvement to this design.

    • Then you would need a isolated power supply for the circuit between the Opto-Isolator and the control circuit for the relay.

      It would defeat your point if you drew your power for the relay from the microcontroller’s power supply.

      I still say if this was design right you would not have to worry about HV feeding back into your Microcontroller. You would have more problems if this design was using a reed relay because of the transformer effect.

  • The board can be improved by changing the orientation of the relay. The wider section (where the JOX-15F sits) should be facing the high voltage terminal block. Then, the low voltage lines won’t be going in between the high voltage track. Even better if the copper thickness is increase to 2 Oz. That tiny blue terminal block definitely needs to be changed to something larger and robust.

  • Great deal! Old relay control PCB is over $9 with all the parts!

  • What is the maximum DC load it can handle?

    • According to the datasheet, the relay can handle 20A on 28VDC. But I don’t know about the traces on the PCB.

      • I bought all the seperate components for this just before this thing came with all the components included, and there was a conversation about the same thing on the pcb page. Apparently, the pcb isn’t supposed to take that much power, and they heat up a lot.

      • This also depends on the type of load, i.e. Resistive or Reactive. The 20A rating is for resistive loads, it can’t handle that for reactive (i.e. Inductive or Capacitive) loads.


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