24VDC to 24VAC?

Discussion in 'The Projects Forum' started by Zapstrap, Dec 26, 2012.

  1. Zapstrap

    Thread Starter New Member

    Dec 17, 2012
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    Once again, after searching the threads, it doesn't look like this subject has been addressed.

    At this moment, my home power system is based on generating 12V. However, I have the capability to change that to 24V, 48V or even 120 or 240AC if I want to spend the big bucks. I don't have the big bucks and debt is our enemy so, I am going to bring the hydro unit's charge rate up to 24V when I get a new 24V inverter in the near future. I have 4 - 6 volt deep cycle batteries that are now in series/parallel to provide 12V. It won't take much to switch them over to 24V.

    Now this brings me to the reason for wanting to convert 24VDC to 24VAC.

    My home security system is all 24VAC. And if I can eliminate the 120VAC to 24VAC transformer, then I should be able to run my security system straight from the batteries, so to speak. It would eliminate a power drain from my system and allow us to turn off the inverter while we are away.

    Any thoughts or suggestions on how to do this? Or even better, where to find such a thing?
     
  2. ErnieM

    AAC Fanatic!

    Apr 24, 2011
    7,395
    1,607
    Does it really need 24V AC, or is 24VAC what is going to it from a wall transformer?

    If the latter, you could most probably just use 24VDC and be done with it. It depends on what the unit is doing with that voltage.

    Got a schematic of the security system or any other information?
     
  3. spinnaker

    AAC Fanatic!

    Oct 29, 2009
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    Not to steal the OPs thread but aren't they the same thing?
     
  4. Zapstrap

    Thread Starter New Member

    Dec 17, 2012
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    This is a pic of the power distribution box. At the present time, I am only using the left side transformer and fuse block. I want to eliminate the transformers...

    [​IMG]

    It definitely HAS to be 24VAC. Most of the cameras are 24VAC. The pan/tilt/zoom camera is super sensitive to the right power! I have fried one PTZ already because this power box is a "universal" 24VAC, which means it fluctuates up to as high as 28V and I have already cooked the sensitive bits in a $1000.00 camera! So I now have a totally separate 24VAC wallwart for the PTZ.

    And, no, no schematic. It is a "cobbled together from used and new parts" system. Some of the cams work on 12VDC AND/OR 24VAC, and some of the peripherals I could get (which I have held back from ordering) like IR LED's are 24/12VDC... It's rather confusing but that's just the nature of the beast.

    Interestingly, the DVR is 12VDC...
     
  5. ErnieM

    AAC Fanatic!

    Apr 24, 2011
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    OK, so the need for AC is real, and to get Ac from DC you need to use an inverter, as you already have.

    While a 24V DC to 24V AC inverter is simpler then a 12V DC to 120VAC inverter I'm not so sure if it is that much more efficient: I literally do not know. If your existing inverter efficiency is the issue then a change may help.

    Do you have any measurements or other observations indicating you are loosing power from the inverter?
     
  6. Zapstrap

    Thread Starter New Member

    Dec 17, 2012
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    0
    No measurements other than observing my home power control panel.

    Our little hydro unit produces 39-41 amps continuously, with 900AH batteries to give us "jam" when we need it. I watch my meters like a hawk, because if we get carried away, we can drain the batteries to the point that the inverter cuts out, @10.5V. So, as you can see, every watt counts. It's a continuous balancing act between how much we make and how much we consume.

    The whole system has been cobbled together over the last 12 years, starting from spinning a home made water wheel that turned a small 12VDC motor and trickle charged an old car battery. A cheap Canadian Tire (aka:Chinese) inverter was added, then a new deep cycle battery, then a few more lights, then a small car alternator, then a satellite internet connection, then another inverter to replace the Chinese one, then the old waterwheel packed it in for the last time, then the new system was put in... then upgraded, then upgraded some more... Dang, that made it all sound so easy:D...

    Here's a pic of the old waterwheel, just a givin er...

    [​IMG]

    And the new one...

    [​IMG]




    Anyway, sorry for wandering there... The transformer for the CCTV uses about 5 precious amps... and if we can eliminate it, we can waste it on something else!
     
  7. Mcestaff

    New Member

    Jun 5, 2016
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    I think ErnieM's original response. Meant that a lot of LV AC equipment works internally on DC. That is, they have internal voltage rectifiers. Therefore, they will work fine with a DC supply. In fact, with such equipment, it won't even matter which way you hook up the positive and negative.
     
    Last edited by a moderator: Jun 6, 2016
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