Particle Photon connected to 3v Relays

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Hi Guys

I’m a new user of the particle.
I want to control a relays directly from the digital pins for the particle photon and i want you re feedback guys for this one:

its relay but connected to an electronic board.
it have vcc input and signal input as well as the main current input and output

Thanks so much


What exactly is your question?
What have you tried?
Have you had a look at any of the tutorials in the docs?

Have you also got GND conneted?


No I want to buy it and i want to know if anybody use it before with a particle.

I want to control a 12V solenoid by a relays.But when i checked for the relays,The most of them are stronger for particle digital it will need a transistor to boost the digital pin signal to activate the relay.but the issue was esthetic.
So It will be better If I found a same système(Relay vs Transistor) but on Electronic board.


This is the important info given on the linked page

To activate the relay from a digial pin it only demands 5mA which is no problem for the Photon (max. 25mA).
But the 200mA stated for operating the relay are drawn from the 3v3 pin which would be too much, given this info

You might be better off with a 5V relay powered off of Vin as long the relay can be triggered via 3.3V logic on the trigger pin.


Thank you @ScruffR for your explanation. Maybe i will try it and i will provide a feedback after that.


Hi Mohammed!
I’ve been using this relay for my projects, they are cheap and worked fine for me:



Thanks @gusgonnet,Is that required to do an I2C connection or the relays is activated automatically when the pin is HIGH?


You don’t need I2C. Regarding to arduino example , when D1 (default pin) is HIGH relay is triggered


Thanks a lot @dreamER


@ScruffR What do you think if i feed the VCC input by 3.3V Power Supply.Do you think its gonna work?


As Well. Did the digital pins fit with the 5V relays Shield even if they have only 3.3V and 25mA Max


I’d not power a 3.0-3.3V reated relay coild off of 5V - they would have rated it higher if it was safe :wink:

The control pin on such relay boards usually comprises an input transistor which won’t pull much current from the controler pin but only switches the supply voltage. The main thing you’d need to “worry” about is whether the 3.3V level is enough for the transistor to reliably switch.


You could also look at:



why dont use a TIP120 rather than a relay? It can handle 12v and the fp is smaller.