Amps VS volts... having a stupid moment

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Toastedwaves

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Hello,

If I join two white wires together, and then the two black wires together, from separate breakers, does that double the voltage or the amp?



(It is computer related. I will have other questions, but decided to deconstruct my question in parts to avoid further confusion on my part..)
 

mmckenna

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It increases the amps. More wire = more carrying capacity. More circuit breaker capacity = more capacity to support load.

But, here is where you have to be VERY careful….
In a home electrical panel, there are usually two "hot" legs. Measuring voltage between them will show 210 volts or so. Touching the two black wires together, fi they are from opposite legs, will create a 210 volt short circuit. There will be much smoke and cursing.
If the two black wires are from the same leg, nothing will happen as they are at the same potential.

Obvious warning applies here, if you have to ask these questions, don't be too proud to call a professional.
 

Toastedwaves

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Hi poltergeisty,

Yes, let me get to the point.

I cannot find/get a laptop charger that will give it enough amps. The original died, and I need a replacement.

So, I thought about buying 2 chargers, joining the output wires together w/w b/b in order to have more amps.

That will not exceed the voltage output, but only the amps.

I need 19v / 6.32a. The universal chargers here are 19v / 4.75a.
 

Toastedwaves

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yes mmckenna, good advice!

Problem is no one can help me with my ideas. I have to do everything myself. Search and find answers. Ask.

The wonderful world of prototypes, I tell ya ;)
 

nd5y

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You usually can't connect two DC power supplies in parallel unelss they are designed for it or isolated properly. Don't be surprised if it doesn't work.
 
F

feets

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Hi poltergeisty,

Yes, let me get to the point.

I cannot find/get a laptop charger that will give it enough amps. The original died, and I need a replacement.

So, I thought about buying 2 chargers, joining the output wires together w/w b/b in order to have more amps.

That will not exceed the voltage output, but only the amps.

I need 19v / 6.32a. The universal chargers here are 19v / 4.75a.
I don't know what your device is.

Amazon.com: Gateway 19V 6.32A 120W Replacement AC Adapter for Gateway Notebook Models: Gateway FX MS2252, Gateway M520, Gateway M520CS, Gateway M520S, Gateway M520X, Gateway M520XL, Gateway M680, Gateway M680E, Gateway M680ES, Gateway M680S, Gateway

SPI R-FSP120-AAC 120W 19V Universal Notebook AC Adapter (Full Range AC Input: 100 - 240 V) - Newegg.com

Power Supply Toshiba 19v 6.32a, Power Supply Toshiba 19v 6.32a Products, Power Supply Toshiba 19v 6.32a Suppliers and Manufacturers at Alibaba.com

http://www.memoryexpress.com/Products/MX18639

Just some results I found searching for 19V / 6.32a power supply.

Prolly cheaper than buying two that won't work anyway.
 

Toastedwaves

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Thanks nd5y, point well taken.

Let me go ahead and ask more questions to help my limited brain comprehend this..

1. Batteries and computer power supply/laptop charger, are both DC output. If I can wire batteries in parallel and increase the amps, I can do the same with chargers. Correct?

2. Voltage is the 'pump', amp is the 'size of the pipe'. Voltage pushes to the computer, amps are pulled from the computer. Correct?
 

Toastedwaves

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Thanks feets, and yes I can search the web too ;)

Don't have a credit card. Things are a little complicated on my side here. Sorry for the the trouble.

I'm trying to do with what I find here, and oh boi, I'm not in Europe or north america... Choices are limited here. I wish I could buy from the web.
 

Toastedwaves

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Just fired an email to the makers to see what they have to say about operating laptop chargers in parallel..

Probly waisting my time as they will answer me with their usual moronic, generic answer. Meh, it was only 30seconds.
 

WB4CS

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Thanks feets, and yes I can search the web too ;)

Don't have a credit card. Things are a little complicated on my side here. Sorry for the the trouble.

I'm trying to do with what I find here, and oh boi, I'm not in Europe or north america... Choices are limited here. I wish I could buy from the web.
Where are you located? I'm not sure about where you are, but here in the US most "big box stores" such as Wal-Mart, K-Mart, CVS, etc, you can pick up prepaid credit cards. In order to keep my credit card info safe when shopping online, I will go to a store and buy a prepaid credit card for the amount I need. Example, pay $100 in cash for the card, and you have a Visa or Mastercard with $100 on it that you can use online.

I wish you good luck with your project, nothing wrong with experimenting and making things work! (As long as you don't burn the house down ;) )
 

WA0CBW

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As the Ghost Busters team was told "don't cross the streams" also applies to paralleling power supplies. Unless the power supply was designed for this it would not be a good idea.
BB
 

QDP2012

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You usually can't connect two DC power supplies in parallel unelss they are designed for it or isolated properly. Don't be surprised if it doesn't work.
Absolutely agree!

Don't be surprised if it doesn't work.
Don't be surprised if it damages the chargers and the equipment you are trying to charge/power.


Thanks nd5y, point well taken.

Let me go ahead and ask more questions to help my limited brain comprehend this..

1. Batteries and computer power supply/laptop charger, are both DC output. If I can wire batteries in parallel and increase the amps, I can do the same with chargers. Correct?

2. Voltage is the 'pump', amp is the 'size of the pipe'. Voltage pushes to the computer, amps are pulled from the computer. Correct?
Not correct. Batteries and chargers do not function the same electrically.
  • Batteries "never" exceed their initial voltage and current. Basically: You connect them, and they start draining. You charge them, and they don't (normally) exceed their rating.

  • BUT, chargers often do have spikes that exceed their baseline rating. Devices intended to be charged often have circuitry to guard against the spikes, but only within the limits of the manufacturer's design.
    The chargers usually are at a risk for spiking at the time they are initially-connected. Usually this is not a problem. But, my point is, a charger, unlike a battery could and often does, even for a fraction of a second, send more voltage and/or current to your device, than the rating printed next to the device's charging-jack.

  • AND, if you take two chargers (even if they are identical and not mismatching in any manner), and you connect them in parallel so that "Charger-1/Wire-1" connects to "Charger-2/Wire-1" so that they send a combined electrical-effort to the "Device/Wire-1", then you also have created a situation where each charger is trying to charge the opposing charger.
As ND5Y mentioned before, if you do not have proper isolation equipment between all of the components, it is a problem!

A circuits-class professor used to tell his class that the first student to smoke their resistors would be nicknamed "Smoky" for the remainder of the semester. But, he also said, with a sly smile that he would give extra points to the student who could put the smoke back inside the resistor. ;)

I hope the manufacturer can help you, because the multiple-charger idea sounds like something you should avoid.

Hope this helps,
 
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Toastedwaves

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Where are you located? I'm not sure about where you are, but here in the US most "big box stores" such as Wal-Mart, K-Mart, CVS, etc, you can pick up prepaid credit cards. In order to keep my credit card info safe when shopping online, I will go to a store and buy a prepaid credit card for the amount I need. Example, pay $100 in cash for the card, and you have a Visa or Mastercard with $100 on it that you can use online.

I wish you good luck with your project, nothing wrong with experimenting and making things work! (As long as you don't burn the house down ;) )
Not going to burn the house down, as everything is made of concrete here in south america, planet of the apes. I did try and get a prepaid credit card, that too, like the rest here is super complicated. Plus they have a 5% tax on money leaving the country, but that's a detail compared to the rest.

Thanks WB4CS! :]


As the Ghost Busters team was told "don't cross the streams" also applies to paralleling power supplies. Unless the power supply was designed for this it would not be a good idea.
BB
ok WA0CBW thank you for the info. Still not clear as to what would happen inside the chargers if I put them in parallel. Doubling the voltage (in series) that I understand, but amps are 'pulled' upon demand, so the amps from one charger will not go inside the other charger, therefore nothing changes for them, except less work for each, trying to feed the monster.

I don't get it.
 

Toastedwaves

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Thank you QDP2012 for all that info.

I have to admit that I still don't understand (not easy being thick) what's the problem charger wise, and yes I did read all your post/explanation. But simply cannot see the problem.

How can one charger try and charge the other one? If that would be true then one charger would try and charge itself also.

Spikes, yeah, that might be a problem (?).

I seriously only see advantages in operating 2 chargers, and do not comprehend what's problem. Could someone tell me what component(s) would 'fry' inside the chargers? That might help me wrap my head around this.

Don't trow stuff at me yet. I'm a little slow and food is expensive.
 

cabletech

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Hi poltergeisty,

Yes, let me get to the point.

I cannot find/get a laptop charger that will give it enough amps. The original died, and I need a replacement.

I need 19v / 6.32a. The universal chargers here are 19v / 4.75a.

So..What make model of computer do you have? Most computer power supplies that I have seen use a supply that has a max of 5a.

Have you tryed going to the manufactor's web site for a replacement?

Most all manufactors have this availablity.
 
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feets

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I need 19v / 6.32a. The universal chargers here are 19v / 4.75a.
19v / 4.75a wired in parallel with 19v / 4.75a = 19v / 9.5a

Do you have access to two 19v / 3.16a (or close)chargers?

If not, the rest is moot.
 
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Toastedwaves

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Toshiba Satellite P850, also known as 'the beast'. Gaming laptop. Can eat most desktop for breakfast. Scary part is even the original charger is not quite up to it.

Yes I did try and get the original charger, but things are complicated here, as stated above. It would basically take months and then they would have probly ordered the wrong charger, or it will be stolen on the way...

Yup, fun fun. Thanks cabletech :)
 

QDP2012

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How can one charger try and charge the other one? If that would be true then one charger would try and charge itself also.
In simple terms, chargers send electricity to something that "has less" than they do--in other words, when a charger has an "excess" of electricity and a discharged battery, or a device, "needs" electricity, then the charger sends its "excess" to the "needy" device.

If you only use one charger, and it attempts to charge a discharged battery, or to power/charge a device, the charger will always be in the situation of "having an excess" when compared to the discharged battery or device.

But, if you connect two chargers together without proper isolation, there will be (many) moments (in the charging cycle) where one charger thinks that it has an "excess" when compared to the other charger, and will try to send its own excess to the other charger.

This is the problem.

In case it helps explain a little more, the charging cycles are patterned after a sine-wave, not a constant-line. There will be times when one charger's cycle is not the same as the other charger's cycle, and if they are not isolated, they will try to "charge" the other charger.

Does this make things any clearer?

EDIT: All of my notes above are discussing two identical chargers. If the chargers are not identical, then the problem gets worse.

Hope this helps,
 
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Toastedwaves

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19v / 4.75a wired in parallel with 19v / 4.75a = 19v / 9.5a

Do you have access to two 19v / 3.16a (or close)chargers?

If not, the rest is moot.
Yes you are correct, feets.

I didn't want to make things more complicated than they have to, but let me explain somethings..

Not only do I have a beast for a computer, but I'm also a computer maniac. I have over 20 USB ports. Running 4 wifi adapters, 2 SDRs, and some other fun toys, conducting many operations at at once. Don't roll your eyes, I'm just a geek.

So yes, a lesser charger would suffice for normal use, agreed, until I resume operations... Then that charger will choke and die, I guaranty you.
 
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