Arduino Mains Failure Battery Backup Circuit
The article explains a simple mains failure backup circuit for providing Arduino boards an uninterruptible supply during such situations. The idea was requested by Mr. Fredrik.
TIC. I thought Arduino was supposed to run off battery in the first place.
http://electronics.stackexchange.com/questions/194537/can-i-use-two-power-source-to-switch-with-a-relay-like-this
http://electronics.stackexchange.com/questions/48577/power-from-battery-when-primary-source-fails
is the second one better?
this one
Is there any problem with this one?
Why use 12 volt battery backup when the Arduino happily runs off both 5 volt (regulated) and 7+ volt (unregulated)?
mollwollfumble said:
Why use 12 volt battery backup when the Arduino happily runs off both 5 volt (regulated) and 7+ volt (unregulated)?
Im going to have a separate 12 v system for my house as well as the grid
but I want to switch over from mains to battery when the power goes off
some things I have running at 12, some at 9 some at 5 usb power and some at 3 and 1.5
just looking at different options
http://www.mini-box.com/s.nl/sc.8/category.13/.f?gclid=CMrN9PWVn8sCFYKavAod23QJ1w
http://www.mini-box.com/Car-PC-Automotive-Computing-Solutions
one of these looks interesting
its a 12 volt PC for your car
http://www.mini-box.com/CarPC-Gigabyte-J1900N-D3V-M2-ATX-HV?sc=8&category=1543
mollwollfumble said:
TIC. I thought Arduino was supposed to run off battery in the first place.
if running off the mains you get a plug pack that steps down the voltage down to 5VDC centre pin positive
if running off a battery you can can use a 9 VDC battery that’s connected to a jack plug positive centre
the arduino when supplied with 9vdc will take it and step it down to 5 VDC using a voltage regulator on the board
CrazyNeutrino said:
mollwollfumble said:
Why use 12 volt battery backup when the Arduino happily runs off both 5 volt (regulated) and 7+ volt (unregulated)?
Im going to have a separate 12 v system for my house as well as the grid
but I want to switch over from mains to battery when the power goes off
some things I have running at 12, some at 9 some at 5 usb power and some at 3 and 1.5
voltages above 5v is just wasting power
I wouldn’t bother reinventing the wheel
BUY something that will do this rather than build it
wookiemeister said:
I wouldn’t bother reinventing the wheelBUY something that will do this rather than build it
Yes. And THEN attach it to the drone.
AwesomeO said:
wookiemeister said:
I wouldn’t bother reinventing the wheelBUY something that will do this rather than build it
Yes. And THEN attach it to the drone.
I want a Bunnings shop where I can buy anything off the shelve!
you might be able to buy a USB hub with battery back up that has a plug to 240
CrazyNeutrino said:
mollwollfumble said:
Why use 12 volt battery backup when the Arduino happily runs off both 5 volt (regulated) and 7+ volt (unregulated)?
Im going to have a separate 12 v system for my house as well as the grid
but I want to switch over from mains to battery when the power goes off
some things I have running at 12, some at 9 some at 5 usb power and some at 3 and 1.5
Interesting. I’ve often wondered what the ideal DC voltage is for running all the less-power-consuming parts of a house.
ideal voltage related to the load there’s a safety factor as well
by rights the higher the voltage the better because less current produces less heat
unfortunately it means more insulation
mollwollfumble said:
Interesting. I’ve often wondered what the ideal DC voltage is for running all the less-power-consuming parts of a house.
2.37854 volts.
I’m an engineer, trust me.
here is an interesting article
http://www.treehugger.com/sustainable-product-design/big-steps-in-building-change-our-wiring-to-12-volt-dc.html
CrazyNeutrino said:
here is an interesting article
http://www.treehugger.com/sustainable-product-design/big-steps-in-building-change-our-wiring-to-12-volt-dc.html
Interesting. Car batteries are a nominal 12.6 volts fully charged. Checking a few “wall warts” in the house yields 10.5, 9, 6, 4.8 and 4.75 volts. The 4.8 and 4.75 volt power sources are not interchangeable. Why isn’t there a darn standard for DC devices?
if you ‘ave two parallel 12V supplies, why bother with a low Vd power mos or micropower relay, just use two diodes with a low forward Vd, one on each supply. Depending on the current, if a single diode has a forward Vd of .2-.3V, so @ 1A current the latter Vd will give you .3W dissipation in the diode (example only). 5A’d be 1.5W, 10A’d be 3W. Typical silicon diodes’d be ~ double that.
you can easy enough add an indicator diode to show which supply it’s running off.
mollwollfumble said:
CrazyNeutrino said:here is an interesting article
http://www.treehugger.com/sustainable-product-design/big-steps-in-building-change-our-wiring-to-12-volt-dc.html
Interesting. Car batteries are a nominal 12.6 volts fully charged. Checking a few “wall warts” in the house yields 10.5, 9, 6, 4.8 and 4.75 volts. The 4.8 and 4.75 volt power sources are not interchangeable. Why isn’t there a darn standard for DC devices?