SparkFun Qwiic Quad Relay

The SparkFun Qwiic Quad Relay is a unique power accessory board that has been designed for switching not one but four high powered devices from your Arduino or another low powered microcontroller using I2C. Taking a look at the board, the Quad Relay has four individual relays rated up to 5 Amps per channel at 250VAC or 30VDC. Each channel also has its own uniquely colored LED, silk for easy identification, and screw terminals for optional connection. Utilizing our handy Qwiic system, no soldering is required to connect it to the rest of your system!

At the heart of the SparkFun Qwiic Quad Relay is an ATtiny84 that takes various commands to toggle the four relays. The I2C address of the ATtiny84A is software configurable so if you had the desire and power, you could daisy chain over 100 Qwiic Quad Relays. There is also a header that breaks out the four I2C lines if you're not taking advantage of the Qwiic connectors. And last up, the barrel jack is rated for wall adapters in the range 7-12V but we have equipped this relay board with a jumper on the underside of the board if you want to use wall adapters at 5V.

Messing with such high voltage is dangerous! We've included many safety precautions onto the PCB including, wide traces designed for high amperage, ground isolation between the relay and other circuitry, and a milled out area around the common pin of the relay. However, with all the safety precautions included with the SparkFun Qwiic Quad Relay, this is still a power accessory for users who are experienced around, and knowledgeable about high AC voltage. If that's not quite your jam, that's okay! Check out the IoT Power Relay, instead, to start learning how to use power relays easily!

The SparkFun Qwiic Connect System is an ecosystem of I2C sensors, actuators, shields and cables that make prototyping faster and less prone to error. All Qwiic-enabled boards use a common 1mm pitch, 4-pin JST connector. This reduces the amount of required PCB space, and polarized connections mean you can’t hook it up wrong.

  • Four JZC-11F Relays
    • 5A at 250VAC, 30VDC
    • Each relay has its own colored LED and silk labels for easy identification.
  • Safey Features
    • Ground pour isolated from relays.
    • Air gap around common pin on the relays.
    • Large trace width on relay pins far exceeding the peak 5A current.
  • ATtiny84A
    • I2C commands for toggling individual relays or all the relays at once.
    • I2C commands for turning all relays off or on.
    • Two I2C addresses
      • 0x6D (Default)
      • 0x6C
    • I2C address is software configurable.
    • All commands are listed in the example code.
  • Screw Terminals
    • 26-14 Gauge AWG wire
  • Power
    • Max Current Draw ~250mA
    • Vin via Barrel Jack
      • 7V to 12V
    • Vin via Barrel Jack w/ Bypass Jumper Closed
      • 5V

Revision Changes: The latest revision includes the following updates.

  • Included a normally closed jumper for the power LED.
  • Switching regulator in place of a linear regulator.
    • The switching regulator is much more efficient; no external cooling needed when powering four relays at once.
  • Improved circuitry around the relays.
    • An issue where relays on certain boards in v1.0 didn't switch completely when actuated has been resolved.

SparkFun Qwiic Quad Relay Product Help and Resources

Qwiic Quad Relay Hookup Guide

January 3, 2019

SparkFun’s Qwiic Quad Relay is a product designed for switching not one but four high powered devices from your Arduino or other low powered microcontroller using I2C.


Looking for answers to technical questions?

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  • fujexo / about 3 years ago / 1

    Got one of the Quad relay boards through a Swiss Reseller. First, the relay worked with no problems for a day or two. Today, I've restarted my Raspberry Pi 4 connected to the board and wasn't able to connect with the python library anymore.

    The module was powered from a MeanWell 12V Power Supply. After opening my relay case up, the Power LED wasn't running so I think the regulator might have released it's magic smoke? Going to test if I can run it on 5V this evening.

Customer Reviews

2.7 out of 5

Based on 6 ratings:

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2 of 2 found this helpful:

Stopped working wth Redboard edge but still works with blackboard

Not sure why, worked for a few weeks of use with an edge but then tried it with the blackboard and it works fine. Tried it again with the edge and did not work....pulled out a second relay board and it worked with the edge. Not sure whats going on.

2 of 2 found this helpful:

multiple problems

This board worked initially using a 12v wall wart, and I could trigger all four relays. Then the power light failed to come on. I thought I may have burned out something because the voltage was a tad over 12v, so I soldered the 5V jumper and powered it with a 5V wall wart, and it began to work again. The next time I tried to use it however, the relay LEDs would turn on but the relays themselves didn't click. So the board is basically useless now.

they keep breaking

I bought 3 of these and two have failed and I don't know why. One stopped being seen by the i2c network. I don't remember what the problem with the other one was. Maybe the same thing. But I just bough another, because it fits my needs well when it is working.

Sorry to hear that you are running into issues with the Qwiic Quad Relay. If you wish to submit a return ticket we can get you taken care of:

stopped working

At first, this worked fine with 12V, but it stopped working on the first day (the relays stopped responding, and the power light wouldn't come on). I switched to using 5V, and three of the relays are working again. However, the fourth relay is unreliable - when you give it power, the other relays click on and off at random intervals. I followed the hookup guide closely, but I'm still giving a few stars in case I did something wrong. Probably wouldn't buy it again though.

Sorry to hear you are running into issues with the Qwiic Quad Relay. If you want to submit a return ticket we can take care of you:

Same issue as mentioned above. Worked for a little and just stopped

I powered with a 9V supply and ran the demo that came with the library for the quad. It cycled the relays for about 2 minutes and then just stopped. All lights went off, and I was never able to get it to run again.

Drats! If you haven't already, submit a return ticket we can take care of you:

Great till it fails

One has been working fine for over a year. One is missing one of the qwiic connectors. That’s ok in this case, but I haven’t powered it up yet to see if it works. One failed after a few weeks. It can’t be reached on i2c. I replaced it with a fourth board, which is working so far.

Guess I’m lucky to have so many, since the board is back ordered.

Yet another one failed. Stopped talking to the I2C controller. And then the one I replaced it with had a badly-soldered I2C connector that flexed up and broke when I plugged a cable into it. The last one from my vast stockpile is working, for the moment.