Solar Panel to Grid Power Switch

Discussion in 'General Electronics Chat' started by marcsota, May 11, 2015.

  1. marcsota

    Thread Starter New Member

    May 11, 2015
    Do you guys know any component that switches from a battery source to grid power if it falls below a certain voltage?
    Im doing a project that has something to do with solar panels. I need a constant 5v source to power a component and I need a switch that closes and changes to grid power when the battery runs out.

    Any helps would be greatly appreciated!
  2. blocco a spirale

    AAC Fanatic!

    Jun 18, 2008
    Bernard likes this.
  3. pwdixon


    Oct 11, 2012
    Perhaps you could use diodes?
  4. AnalogKid

    AAC Fanatic!

    Aug 1, 2013
    Please clarify what you mean by "power grid." If you mean the AC power coming out of the wall, this is not a trivial task, and involves dangerous high voltages if you want to build everything yourself.

  5. Papabravo


    Feb 24, 2006
    If you have +5VDC from two sources, a battery and a mains powered power supply, then diodes can be used to select the source with the higher input voltage.

    Your question was a bit unclear since you mentioned solar panels and some people want to feed the power grid from their solar panels. This is the complicated problem mentioned by AnalogKid.
  6. MikeML

    AAC Fanatic!

    Oct 2, 2009
    How much current does the load require?
    How much current does the solar panel produce?
    What is the battery chemistry? (the cut-out voltage must be set to protect the battery from being over-discharged.)

    There should be a higher cut-in voltage (hysteresis) to allow the battery to accumulate charge before it picks up the load the next day.
  7. Hypatia's Protege

    Distinguished Member

    Mar 1, 2015
    Your inquiry is ambiguous...

    If you are referring to the transfer switch itself, be advised that it must be configured as a feed - selector -- lest you risk 'phase clashing' (a 'contest' you just can't win!!! ;););))

    If, on the other hand, your reference is to DC power or DC control signals, "diode OR-ing" (as described elsewhere on this thread) is satisfactory provided that, in the case of DC power, the current is such that dissipative losses are tolerable...

    Best regards