About the last post - the truth is i dont have weeks to purchase new device and i really dont understand what this can help me;
If i understand right you offer me a device with i can measure how many A provides really the charger X,Y or Z.

What is the logic to buy 2A charger when 1A worked seconds and then explodes? Wouldn`t be effect the same ?

The meter measures what the load draws, not what the charger can put out. I don't know if it will fit your needs or not.
If your device draws 1.5 Amps a1 Amp charger might blow up but a 2 Amp charger will hold up okay.

 

Mhm.

That`s good. When i have some money maybe will write you to tell me more

 

Mhm.

That`s good. When i have some money maybe will write you to tell me more

I found somebody with a tablet. Yes, it uses a 2 Amp charger.

 

450 mA is what my old cell phone draws when charging. To tell the current draw I hook it up to 1USB port with a USB meter. I got the meter from Electronic Goldmine for about $10.00. Part number G21309 I think it was.

Can you give me the exact model of the device? I will search world online shops for it.

Questions 2 and 3 :
How to right discharge the battery if i disconnect it from the tablet ?

I have reRead the whole thread and saw that the battery can be charged seperately without board. Can you tell me more

 

Hi there.
Have one piece here. The microusb port is gone as option. I saw the jack power supply ability. Took one Nokia charger(new from store)5v but i see it`s 450mA. I ve heard that when the battery is totally discharged it has to be bringed back to life with 500mA charge. Are these 450mA enought and how many hours to wait for effect? If i put it now for charge in 12:30 is it problem if tonight is not ready to wait for tommorow morning - 10 for example?
The battery has controller yh/maybe "M"/-jz-5045-c

Greetings.

I have tested my phone charging a couple of days ago and this is what i observed...

When the battery of my phone is charges is low like 6% - 15% the = the amp draw around 500 Amp to 550 Amp...as the charges increased the amp becomes lower...as follows

20% - 35% = 480 amp to 470 amp
39% - 43% = 450 amp
44% - 50% = 440 amp

Despite i didn't completely finished observing it ...but i believe as the charges increased the amp will decrease. Maybe at 90% it should be around 270 Amp the last time i saw it.

So basically as the battery charges getting full the resistance increase.
However this is my phone...i believe different device has different amp draw...and also depending on the charge some chargers are faster while others slower.

 

i put new charger 5v/2a
without load :
5.40v
-0.009A

3.713v in the begining of the charge

 

i put new charger 5v/2a
without load :
5.40v
-0.009A

3.713v in the begining of the charge

It's normal when there is no load there shouldn't be any amp measured because there is no resistance only when there is load then the amp can be measured.

What is 3.713v is it the load voltage or the power source to charge the load?

 

What is 3.713v is it the load voltage or the power source to charge the load?

The voltage of the battery.

 

That's normal.

 

enough to boot/power ?

p.s when i measured current my sonde(i hope that`s the correct word) was in wrong place - the positive was in V Om plug not in A

 

enough to boot/power ?

Yes, I think you were measuring the voltage of the battery under charge? The voltage you see will be dominated by that of the battery, not whatever is going on inside the charger. The battery voltage should increase when the charger is applied.

p.s when i measured current my sonde(i hope that`s the correct word) was in wrong place - the positive was in V Om plug not in A

I think "probe" is the word you want. The metal spike at the end of your meter's wire? You cannot measure current without the cable in the right hole on the meter. I'm not sure what you measured.

 

i think there`s something wrong with the battery.
Maybe many hours charge and when i unplug the charge the V is 3.06 which most likely is not enough to power on the tablet.
So...
"How to right discharge the battery if i disconnect it from the tablet ?"

 

You don't want to discharge the battery, you want to charge it. Whatever you tried sounds like it didn't work. Your tablet may not have recognized the charger and did not allow charging. It's difficult for us to tell what you are doing.

 

theoretically if i want to do discharge is light bulb good option ?

edit the battery voltage is increasing when plug it to the new charger(i think 5/2)

how many hours to wait for full charge ? now is 12:16 local.

 

Hi there.
I wanna UP thread for one reason.
I work in service and if want to wake up device which doesn`t accept charge from the wall i use the notebook usb port.
If i have more devices to wake up at once can i use wall charger 0.5A? Should i pick something not cheap?

 

I have no idea what you are asking!

 

enough to boot/power ?

p.s when i measured current my sonde(i hope that`s the correct word) was in wrong place - the positive was in V Om plug not in A

Ammeters go in series with the load. Usually there is a fuse in the meter that blows.
Ohmmeters are not to measure powered circuits.
Voltmeters go across the loads.

Devices specifically desgned for USB like this https://www.amazon.com/dp/B00J3N2JKY?tag=bing_ads-20 can help a lot.

 

Hi there.
Have one piece here. The microusb port is gone as option. I saw the jack power supply ability. Took one Nokia charger(new from store)5v but i see it`s 450mA. I ve heard that when the battery is totally discharged it has to be bringed back to life with 500mA charge. Are these 450mA enought and how many hours to wait for effect? If i put it now for charge in 12:30 is it problem if tonight is not ready to wait for tommorow morning - 10 for example?
The battery has controller yh/maybe "M"/-jz-5045-c

Greetings.

Most of these chargers are SMPSU - they sense overcurrent and inhibit the oscillator. Of course when the oscillator stops; there's no power conversion and the overcurrent disappears. So they pulse on and off - the off periods mean no charging, so a wall wart that can handle the current draw will do the job a lot quicker.