Power source for relay actuator

[Moshe Livne]

I am building now some relay boxes to turn my outside lights on and off. as I am going to route 220v into the box it seems a bit silly to use batteries. I am using nano so a module that converts 220v into 5v with usb out would probably be the best. tried finding it on aliexpress but I am probably using the wrong terms. I know that I can probably take the module out of a cheap charger but if someone knows of reliable good power supply like that I would appreciate the info.

Thanks,
Moshe

[hek]

"buck converter" is a good keyword.

Like this (I have no idea on the safety on these thought)

http://www.ebay.com/itm/12v-5v-3-3v-9v-AC-DC-Power-Supply-Buck-Converter-Step-Down-Module-/131380498361?pt=LH_DefaultDomain_0&var=&hash=item1e96e34fb9

[Cory]

I usually search for "ac usb" on ebay and get good results.

So far i have been happy to find chargers like these. They support up to 240V and are small enough to fit into electrical boxes with the case on.
http://www.ebay.com/itm/New-US-Plug-USB-AC-Wall-Charger-Adapter-For-Samsung-iPad-iPhon-White-f20-/281681762352?pt=LH_DefaultDomain_0&hash=item41958a9830

I typically get them for ~$0.70 each but have also won some bids for less.

[Moshe Livne]

@hek Thanks! its amusing though that these are not cheaper than getting a wall USB charger... the miracle of consumerism i guess.

[Mickey]

@Cory said:

I usually search for "ac usb" on ebay and get good results.

So far i have been happy to find chargers like these. They support up to 240V and are small enough to fit into electrical boxes with the case on.
http://www.ebay.com/itm/New-US-Plug-USB-AC-Wall-Charger-Adapter-For-Samsung-iPad-iPhon-White-f20-/281681762352?pt=LH_DefaultDomain_0&hash=item41958a9830

I typically get them for ~$0.70 each but have also won some bids for less.

those modules not so safe to be inside a 220v box without ventilation they can burst in flames (its rare but imagine it happen once in 220v box and the all house could burn...) I open one once to see how can they fit in so small box and they just cut the PCB on half and connect one half to another with ribbon cable and fold the 2 pieces on on another with a thin foam to protect the capacitors...