Increasing Amperage of a Power Supply?

Discussion in 'The Projects Forum' started by aq_rules, Oct 23, 2012.

  1. aq_rules

    Thread Starter Member

    Oct 28, 2009
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    Issue is, I can't get a 5 VDC 3A 15W Power Supply here where i live...but i have two supplies of 5v 1A....Now what m trying to do..i guess u guyz got it....Please help..

    Its power supply of Actiontec MI424WR Verizon FiOS Router...living without wifi on my mobile devices is rlly difficult:p


    Please help..i noe that amperage depends upon transformer installed in the supply but let me noe how to chk its amperage...and is there any way out by placing sum resistors or transistors etc??


    Waiting:(
     
  2. wayneh

    Expert

    Sep 9, 2010
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    And where is that?

    Finding the right supply is worth far more effort than trying to change an existing one, which is probably not possible.
     
  3. aq_rules

    Thread Starter Member

    Oct 28, 2009
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    Karachi, if ur opinion could solve this issue thn i must not be here:( i have tried.....now dun tell me to buy from some link or new sources plz...help me with what i wnt
     
  4. wayneh

    Expert

    Sep 9, 2010
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    OK, let's back up and understand what you need to power, and exactly what you have available.

    Do you need a regulated 5V supply, or just a "wall wart" 5V DC. A wall wart is just a transformer, sometimes with a rectifier and filter capacitor. They usually produce a much higher voltage at low current, but will supply the rated voltage at the rated current, more or less. A regulated supply is more like USB power - very narrowly controlled at 5V.

    The supplies you have - are they old fashioned heavy transformers or are they small and light, switch-mode power supplies, or SMPS?
     
  5. gerty

    AAC Fanatic!

    Aug 30, 2007
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    And what happened to the original power supply for the router?
    If the router has a problem (short?) you'll just burn up the new power supply.
     
  6. Papabravo

    Expert

    Feb 24, 2006
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    In short you cannot do what you want to do, which if I understand correctly is to take a 5V 1 Amp supply and make it deliver 3 Amps. The first step would be to replace the transformer and then redesign the regulator to control a series pass transistor that could handle the current demand.

    If you take two supplies in parallel with a current sharing resistor between them you can get 5V at 2 amps but that is still not 3 Amps.

    Depending on your skill level you might be able to adapt say an 8 volt 5 Amp supply to one that will deliver 5 volts at 3 Amps. If you're a crackerjack analog designer and can wind your own inductors you can build your own SMPS and convert any supply with greater than 15 Watt output to something that will meet your requirements. Getting the right parts is still going to be a problem -- I'm guessing.

    Please understand that IMHO you will spend 10 times the hours and units of currency trying to modify the existing power supplies. You need to find or salvage something that meets your requirements. There is just no substitute for the right part.

    You can of course also continue to engage in magical thinking and hope for a miracle. Perhaps that will work.
     
    Last edited: Oct 23, 2012
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  7. wayneh

    Expert

    Sep 9, 2010
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    As I suggested earlier, your time will be better spent searching for something else.

    Did you know that just about any old computer will have a nice power supply that is more than enough for this? Perhaps you can find one on its way to the dump.
     
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  8. aq_rules

    Thread Starter Member

    Oct 28, 2009
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    thank you for replies......i thought there might be sum easy way...well thanks alot...i guess i've to start hunting the city for this:D thank you papabravo thank you wayneh
     
  9. RV9Factory

    New Member

    Oct 27, 2012
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    He may have had the same problem I did... Verizon sent me a new power supply (was wall wart) and told me replace existing. Out of the blue - I didn't ask for it. When I went to replace it, the original was very hot and one side of its plastic body was deformed. I had had it for a few years with no issues I know of. I'll bet they did a firmware upgrade that increased the power consumption of a GPU or something and pushed a marginal power supply over the edge.
     
  10. NFA Fabrication

    Member

    Aug 12, 2012
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    This is not a group of your personal servants, so I'd lose the attitude. People here are very nice and are usually more than glad to help, but acting like that when asking for free advice seems pretty arrogant to me.
     
  11. Papabravo

    Expert

    Feb 24, 2006
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    Well I did not take it as arrogance, but frustration with trying to do first world engineering and procurement in a third world country. He was looking for a way to deal with facts on the ground that he well understood. Unfortunately there was no clever magic we could offer that could extricate him from his situation. He might not like that answer but at least he tried.
     
  12. NFA Fabrication

    Member

    Aug 12, 2012
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    You are not really in a position to take out your frustration on forum members that are trying to help, just because they don't give you the exact answer you are looking for. I felt it was a very down to earth logical reply and makes sense, just because it is not what you want to hear, didn't make your reply appropriate.
     
  13. Papabravo

    Expert

    Feb 24, 2006
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    @NFA -- Was your reply directed at me or the OP? I have no frustrations whatsoever. I was trying to explain my view that the OP was unhappy with the situation in his country where he could not acquire the materials he needed. I don't understand why anybody thinks arrogance was involved. It is just my opinion after all. Maybe it counts for something and maybe it doesn't.
     
  14. NFA Fabrication

    Member

    Aug 12, 2012
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    The way it was worded, it sounded like the same guy, my mistake. People getting an attitude towards others trying to help should be a ban-able offense as far as I am concerned. that's all i was getting at.
     
  15. Papabravo

    Expert

    Feb 24, 2006
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    I don't disagree with that point of view, but I think we need to avoid a rush to judgement. I give the moderators high marks for applying the stated policies in an even handed matter. If it is a question of "tone"; we need to go to the motivation of the speaker. We clearly had different opinions on the OPs original motivation for his statements. We should be careful about waving the "arrogance" card lest we be tarred with the same brush. That is all I am saying.

    For the record I think people in third world countries trying to do technology is an awesome testament to the human spirit that will not be put down: not by problems with governments, not by problems of transportation and trade, not by problems in the movement of funds. In short absolutely nothing will stand in their way, and I fell honored to be able to help them in their quest.
     
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