hi guys, just joined the forum. I hope is the correct section to write and ask help about my project.
i have arduino nano to be used as wireless node for switching on or off a relay(in parallel with manual 3 way switch). i checked the power consumption for both rf and realay and, since the relay could be in the on position for many hours, its not convenient to power the node using batteries(i dont wanna change batteries every week). I was thinking to use a mobile phone usb charger to power the nano but i dont think the 5V are stable(i paid it 2$). how can i easily have 5V stabilized from a not stabilized one?Or maybe how can i bring 5V down to3.3V stabilized? Please let me know if anybody of u knows a cheap solution.
Furthermore my project is easy: i wanna switch on or off lights both from pc(arduino connected) or by hand? what is the best solution?i cant use a servo, so please not propose it. Right now im using relay.
Thanks
Furthermore my project is easy:
You are probably wrong on that part.
maybe not , i just need a continuos power supply. any concrete help?
The 5V produced by almost any phone charger will be sufficient for an Arduino Nano. It does have its own power regulator on board so it can handle up to 20V spikes from the charger and dropouts that don't go below 3.3V for more than a microsecond can also be tolerated.
You may have a non-functional charger which goes outside those limits, so then you get to spend another $2 to get a working one. If it kind-of charges the phone, then it will definitely run the Nano and the relay.
MorganS:
The 5V produced by almost any phone charger will be sufficient for an Arduino Nano. It does have its own power regulator on board so it can handle up to 20V spikes from the charger and dropouts that don't go below 3.3V for more than a microsecond can also be tolerated.
You are getting muddled. A common phone charger nowadays is s switchmode regulated 5V supply, so you feed it into the 5V terminal. It is not then protected against voltage spikes.
If you want to feed power via the regulator through Vcc, then you will need a minimum 7V and a phone charger of the common sort will not do.
arj44ac:
I have Arduino nano to be used as wireless node for switching on or off a relay(in parallel with manual 3 way switch).
That actually sounds like a bad idea. Not only do you have the concern about holding the relay on for extended periods - which means you need continuous power but frankly, you need continuous power anyway - but more to the point, you don't really know whether the light is on or off.
Perhaps you figure that you are only ever going to be in the same room with the remote so it does not matter, but in general, it would be better to arrange it so the light is controlled directly by the relay, and the remote and the light switch have defined "on" and "off" controls.
Thanks for the infos.
In my project i can say if light is on or off by a AC sensor before the bulb and light sensors in the room.
wht "A common phone charger nowadays is s switchmode regulated 5V supply," s switch mode means?
Furthermore my room has two 3 way switches already and pass to a button+relay system is not feasible...would have been perfect!
So wht u guys suggest to have in parallel a remote controlled node with hand 3 way switches?
thanks
A switchmode converter or regulator operates by rectifying mains (if that is the input) to DC (with reservoir capacitors) then "chopping" that DC to AC at a high frequency which means it can be changed to a different voltage using a very lightweight transformer (due to the high frequency), then rectified back to DC of the desired voltage.
The duty cycle of the "chopping" is controlled by a feedback system according to the output voltage, so that voltage is inherently closely regulated (although the same general process is used without regulation or subsequent rectification to DC in Compact Fluorescent and some LED bulbs). So lightweight "phone chargers" rated at 5V are generally sufficiently close to 5V to provide Vcc directly. There is admittedly some risk involved as they generally do not include proper over-voltage "crowbar" protection if the regulating mechanism should fail - as it sometimes does.
Please supply a drawing of how you intend to connect the relay to the existing switches. You can draw it on a sheet of paper then photograph it.
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