Electrical Wiring in the Home/electronic wiring help


So I have 2 cellphone chargers that output 5 volts at 2 amps.  I want to combine them so that I can get more amps if any. How and what do I use to wire them so that it will charge my phone.

Frank,   I take it both the 2 mp chargers are made to charge that phone,    and most likely you bought another thinking the first was not doing the charge correctly        Am I close?

Here is the problem,   first you could put the two charger outputs in parallel,    in other words  one plug in would be in the phone,   then the second pair of wires,   you would keep your polarity right   tap into the first and now you would in theory have 4 amps,     

Instead of me writing all the electrical theory out,  here is link explaining it all


But I am concerned we have a problem here that is not current,      

Also  chargers even rated exactly alike        will not charge exactly alike,  and one will sense it is done before the other,,  then  now we have a tapped in parallel connection but one of the chargers is likely to try and back feed into the other,  and they have all kinds of different circuitry in chargers,     none are the same,     

If your OEM original charger is not charging your phone,   it is likely that the problem is not the amount of current      

If you watch an amp meter on a battery charger        when you first start it     it might put out 20 amps   depending on the battery, conditions,  so on,   and as the battery becomes charged the amps drop off,       

So you would be charging at two different rates      again even with exact chargers,      they are just not made with that close of tolerance,      

If your one charger is not charging at all       then it could be the battery is bad,  has developed a memory  and only charges to a certain point,  much lower than the original capacity,       

Normally the best way to charge a battery is slow,  and constant, and repeated in the same manner,

You might want to read through this


In the phone itself,  there are all kinds of detectors [for lack of a better word]  that measure the incoming voltage, current, temperature, rate of charge, amount of trash in the DC signal,   [trash is basically  AC that is not filtered out by a rectifier device,     so if you looked at the charge signal on a scope you would see AC   "RIPPLES"  in the signal,   

Too much trash and some devices shut off the charging incoming,       or if the phone detects any other issue the engineering was concerned with.

The battery itself also has overload, voltage and other protection circuits or a chip imbedded in the battery,     too much initial current could turn off the charging system in the phone and maybe even the battery,         

Bottom line,  the charger designed for the cell phone should charge the phone at a reasonable rate of time, and at the matched specs it was designed for,   

In theory  I see where you want to go,   and on a simple electrical circuit   not a problem,   but it gets way complicated when you get into cell phones and cell phone batteries with micro charging circuits,       

You didn't say why you wanted more amps,     are these chargers not designed for your phone?

At the prices they charge for cell phones,  I would be very careful to not plug anything into the phone that is not what the phone was designed for,  it is not a simple OHMS law kind of thing,    

more of interest


AND finally   a complete link to battery charging technology


I see where you want to go,  I just don't know all the particulars,  if you have no charger an are wanting to make one,  or one is not fast enough,    or doesn't charge completely,     

The whats and whys are important,     if you had one charger and it just did not do the job I would say you have a worn out battery,  bad charging circuit in the battery, in the phone, or both,    

But if you are just trying to get to 4 amps,   because the phone data states four amps,  how those four amps are delivered vary greatly from charger to charger and phone to phone,     

Unless you have schematic of the phone circuit and know all the specifics,   the amps is just one tolerance of the phone,  and a rough on at that,       

Charging batteries the wrong way, can cause all kinds of problems from overloads to fire, to a blown up $700 phone,

In theory I am not saying it is impossible, but unlikely   

I would suggest an OEM charger from the manufacturer,    and a battery from the manufacturer,     or a known generic charger that warrants it will charge a list of phones and yours is on that list,       there are generics out there for specific phones,      and all in one storage cells you can precharge,   and use as needed,    

But if you are attempting to make a four amp charger out of two    2 amp chargers,   just too many complications and dangers to be fooling with,        

If you want to give me the phone specs, and th4e charger specs, I will dig into it for you, but my guess is we will find that the two chargers in parallel will fight each other,   and without a complex way to balance the charge  plus blocking any back emf to either charger,   and to make sure we don't immediately overcharge the battery and blohw it out of the phone,     

I would get with the manufacture and get the correct charger   and if there are problems from there,   let them correct the issue,        

So I would Not  NOT    simply wire the outputs in parallel and plug it in,      that would be how it would be done physically   but with the circuity we have no idea about in the phone or the battery,    I would not chance it,      

A much safer way would be to find a regulator and use batteries as a charger     that way no rectification,    and then charge the   "charging batteries"  by using rechargable batteries as your charger,   


Above is an interesting generic charger,  and it shows all the whoops you have to go through to find the right connections on the battery, the configurations and so on,        

I think something like that would be a much better choice,  as connecting two chargers blind is likely to have a ton of bad issues,     right in theory,  if you were dealing with a simple battery sitting on a bench,  but this is a whole different ballgame      

Let me know how you get along,    but again my suggestion is to go with the OEM CHARGER     and not chance damaging your phone or a fire, or many other issues,  based only on AMPS  
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Will Babbitt


Electrical issues of all types, wiring, control, appliances, components, specialty in Electric MOTOR or APPARATUS trouble shooting, electric motors, electrical problems, single phase, three phase, DC, capacitors, elevator MG-Sets, modifications, reverse engineering, VFD Drives, single to three phase convertors. Repair of most any electrical/mechanical/electronic apparatus, OEM, AC, DC, Industrial Applications, Three phase, single phase failure mode, determining the root cause of the equipment failure BEFORE failure repeats, Antique appliances, electric motors, fans, ceiling fans, base mount fans, poor equipment performance, Modifications, habitual failures, vibration, redesign, obsolete issues, collectible items restored, rewinding. Owner of EMR Repair Inc www.emrrepair.com More information on electric motors, under Engineering/Motors Ask about any electrical or mechanical problems in the home, office, or even at your work. B2B or business to business CONSULTING I can do but it would be a much more complex issue, that would require a significant amount of time. repair@mearservice.com from there we can discuss and begin work on about anything. Industrial electric motors, controls, troubleshooting, vibration, alignment, any type of industrial or commercial electric/electrcical equipment For the home owner, renter, apartment if you have odd things going on, describe to me, photos are normally very helpful, appliances, heating and air conditioning issues, light switches, installation, DIY PROJECTS FOR THOSE NOT EDUCATED IN ELECTRICAL, we can do some things, but for safety and sanity reasons, I may refer you to a local electrician, and help you find one, help you with pricing and even speak directly with anyone you hire if you have issues,


Over thirty years with a major repair and sales company, VP of Operations, and former owner of my own specialty repair shops, MEAR Services local to Kansas City Missouri EMR Repair Inc., located in Kansas City Missouri, 2014 sold both businesses to JCI Industries, Lee's Summit Missouri wbabbitt@jciind.com Evaluation and repair of electrical/mechanical apparatus. Electrical and mechanical repairs, trouble shooting including, vibration and balance issues. About.com provides this service, and the huge costs to provide help on about any subject. They provide the servers, the people to vet the experts, costs that would be the same as operating a good sized business, They should be appreciated for what they do, the huge costs and the great help they provide for free, Electric motor questions, can be answered here but there is a dedicated category that has other experts to help and add to a solution. Other common questions, are noises in the walls, breakers tripping, devices not starting or shutting down for no apparent reason, smoke alarms buzzing, thermostat change outs, or sizing wire or needing information for a new project, but anything can be resolved, anything, with enough effort and patience, DIY, with electrical is possible, but in most cases the use of a simple ohm meter or volt meter is needed, they can be purchased at any hardware store for a few bucks. If you have smoke, or smell smoke, don't be writing me, call 911 the Fire Department has no problem looking for smoke smells, better then spraying water on a blazing fire. DO NOT GET CAUGHT INVESTIGATING AND TRAPPED IN A BASEMENT LOOKING FOR A BLOWER FAILING< As to the tip jar, it is up to you, it is appreciated, every expert spends out of pocket that I know, we spend on IP time, computer wear, printing documents, books, and of course our time, but if we prevent a $400 service call, we did well,

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10 plus years, various Technical Schools, followed by Industrial College Credit and non Credit Courses, electronics courses, experience in most any electrical apparatus, electric motors and generators, AC OR DC, fractional to above 5000HP, other electrical apparatus, slip rings, sleeve [plain] bearings, lubrication, identification-no data plate, control components, service and sales. I have continued night schools for decades, the list is extensive. I have been in the business of repairing most anything with wires or mechanical parts for decades, I have some helpful hints and directions you won't have to dig up. Or hopefully not have to pay a huge service call invoice to find.

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