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Can anyone make an R11 feed power supply to charge a 24VDC battery?

Discussion in 'Alternative Energy' started by SsgKen, May 2, 2009.

  1. SsgKen

    SsgKen New Member

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    I have an off grid cabin. It has golf cart batteries in series for 24 volts which feed a Trace inverter. I got the telephone company to install the phone line for which I pay monthly. I do not use it as much as I would like. I understand the line voltage is higher than 30 volts and as high as 70 (vac I think).

    Can anyone tell how much current can be pulled off of one of these if the proper device is installed? I am paying for the service including about $17/month in taxes and fees. I do not think i would be stealing their power. If I lived there full time I would pay the same and use a lot more power. This is located in Wisconsin, USA.
     
  2. Willbe

    Willbe New Member

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    The Telco line is ~56vdc [4ea. 12v batteries being float-charged] at ~170mA, max.
    If you took power from the line the Telco would probably think your phone is off the hook.

    I think C/20 for your golf cart batteries is a lot more than 170mA. It's probably more like 5A. Perhaps you could charge a small battery overnight with the Telco line and then discharge it into the 24v batteries, but 170mA for 8 hrs is not very many amp-hours.
     
    Last edited: May 2, 2009
  3. SsgKen

    SsgKen New Member

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    thank you

    I have seen people charge cell phones and I wondered if there was wany "REAL" power in the line.

    ty
     
    Last edited: May 2, 2009
  4. dave

    Dave New Member

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  5. Sceadwian

    Sceadwian Banned

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    It MIGHT be enough to counter the battery packs self discharge rate though.
     
  6. Torben

    Torben Well-Known Member

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    Besides the minimal current you'll be able to draw, you'll have to deal with the fact that the phone company closely monitors the current draw on phone lines. They will notice, and they will ask you about it, and they won't like it.

    Plus, just look at the cabling in the phone line. You might trickle charge a battery without melting them but you won't do much else. A much better bet would be wind or solar (or both) charging your batteries.


    Torben
     
  7. tcmtech

    tcmtech Well-Known Member Most Helpful Member

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    Don't the phone company control systems drop the line current to a few ma level when there is an extended "short circuit" condition?

    And how cheap are you when you feel the need to try and charge batteries off of a phone line? :p
     
  8. Sceadwian

    Sceadwian Banned

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    Depends tcm, if the batteries weren't used for extended periods of time the small current he would be stealing would keep the self discharge from occurring and him walking into a house with dead batteries. I doubt you could 'charge' much more than a AA or so with it.
     
  9. SsgKen

    SsgKen New Member

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    Having a phone is not cheap

    I have PV panels. I did not get down to telling the exact location which is less than 30 miles south of Lake Superior. From Dec 10 to Jan 20 or so, there is no insolation to put the amp meter above zero. I make a "donation" to support rural ISP and long distance if you can believe the Gov. is actually putting aside the taxes and fees for that purpose of about $200 per year. I would be cheaper off if I dropped the land-line service and paid someone to snowmobile back there with a few gallons of gasoline to run the generator for a few hours around New Years Day. I could then hope the iffy cell service is working.

    With 300+ inches of snow only the wall mounted PV panels put out any power at all when the snow falls off due to the vertical angle. Wind would be torn off its moorings without supervision.

    On another line. Is there enough power in a phone line to run a LED nightlight or charge a cell phone. Can the power be regulated to take only what Ma Bell would not care about?

    Another note: I am on my second 12 phone main entrance box. I was wired for 12 lines in case I wanted to put in a bed and breakfast or so they told me. Phone was installed in 1992 and by 1999 I was down to my last unfried input. 11 were nuked by lighting along with two computer modems, one laptop, and a dozen ten dollar phones. The ground was checked every time but with 17000 feet of buried line it must pick up enough lighting to defeat the grounding system. I talked with an IEEE man but with five patents he could not bring down "ground rod sphere of influence" to language I could understand. I think he was trying to tell me that without a perimeter grounding system, I was a goner.
     
  10. Sceadwian

    Sceadwian Banned

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    Ground rod sphere of influences means you need a better rod. If you want to protect an area 100 feet in radius you need a 50 foot long rod, or multiple smaller rods.

    You should easily be able to charge a cell phone or power small LED lightning but like will said, if you try to draw any power off the line it's going to go 'off hook' The phone company shouldn't care either way but you're not going to get phone calls in.
     
  11. SsgKen

    SsgKen New Member

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    Ground rod sphere of influences

    Thank you. Now I understand it. I guess since MA Bell kept sending a man out, they did not care about his time, only if he had to install a better ground. His name was Guy. Nice fellow. He told me each time he fixed it that he tested the ground and it was within specs. This question may deserve its own thread.


    The phone is unplugged when I am away so they are not fried when lightning hit somewhere on my road.
     
  12. mneary

    mneary New Member

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    Have you considered a SMALL wind powered generation system, say a foot or so off the roof? I'm told there are rotor designs that are resistant to overspeed.
     
  13. SsgKen

    SsgKen New Member

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    This was partly a thought experiment. There is no real reason that the batteries cannot sit slowly discharging for six weeks in below zero weather. If anyone doubts the Die Hard commercial where the car sits on a frozen lake, it is true. However put that car in Death Valley for a month or two and it will be dead.
     
  14. smanches

    smanches New Member

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    Just out of curiosity, exactly where is your cabin? I grew up in Marquette. :)
     
  15. SsgKen

    SsgKen New Member

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    Twin Lake
    Cramer Lake rd
    Mercer, WI 54547
     
  16. SsgKen

    SsgKen New Member

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    There are tall pine trees around the house. To do anything they should be above the trees. Way too much of everything. To do a lot they should be 80 feet above the trees. The pines will continue to grow 16 or more inches per year for another forty years.. It would be a race I will lose.
     
  17. Sceadwian

    Sceadwian Banned

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    Psst... Suggestion.
    Put one IN the tree =) The pole will grow with the tree, I've heard of people doing this for lightweight ham antennas before, but keep him mind you'd have to put a lightning arrest on the whole thing.
     
  18. SsgKen

    SsgKen New Member

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    If you are young, carve your name in a tree chest high, it will be there chest high the day you, or the tree dies. Trees grow from the top. If I put it on the top. It will be ten feet below the top in seven years.
     
  19. Sceadwian

    Sceadwian Banned

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    Not if you put it on a 10 foot pole. Then you only have to go up there to move the pole every 7 years.
     

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