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-1

Contrary to what other's have stated, unless you plan on wiring the relay directly into the mains, I do not believe your idea is that dangerous if you follow this advice carefully and gather some knowledge first. First and foremost, never wire live cables. Never touch live wires, or leave them exposed, in any circumstance, unless you are a trained ...


4

I would recommend a transistor - not only does it reduce the current required but it isolates the Pi from the relay which helps to ensure that the Pi is less likely to suffer damage. Is this just a relay that you plan to drive directly? Don't forget about the reverse EMF that occurs when the relay is de-energised - it will generate a high enough voltage to ...


2

In the comments, you may have gotten the advice not to start soldering with mains. I would agree with them, though a solution exists. In my home I use a remote controlled switching system, based on 433MHz. What I have is called "Klikaanklikuit" and the website of the vendor boasts that it is also available in Spain. But others exist. If you wire a ...


3

Driving the coil of a relay requires power. Power (P) - in direct-current electrical form - may be calculated as the product of voltage (V) and current (I): P = V * I Knowing even a little bit about the GPIO specifications, and then looking at the numbers in your table, it is clear that the RPi Zero is simply incapable of supplying sufficient power to ...


-1

This is a common issue (3.3v pin cannot reliable control a relay). The Pi does have a couple of 5v pins -- but those are always on (basically a pass-through of the 5v power supply). Typically a circuit is needed where you use the 3.3v pin to control the flow of the otherwise always-on 5v power. The 5v power throws the relay. That's the basic idea but there ...


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