SternWake
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This might be better off in the Products subforum, but I think it might reach more people on the electrical forum, but Mods, do as you wish with its location
Many of you wonder how much your USB devices consume.
Wonder no more!
http://www.amazon.com/Jelly-Comb-Un..._sim_hi_3?ie=UTF8&refRID=0J6JSC47VP70W55RRM2X
It is an Amp hour counter too so one can see how much it consumes over a given period of time.
However one must remember the Mah figure is at 5 volts, and is not representative of the AH figure as if it were at 12 volts, but figuring in conversion inefficiencies, one might get away with doubling the Mah figures. 1000 Mah =1AH if the voltage is the same.
What i have found interesting with the product, it the output voltages of various USB power supplies, and how it affects the charging of the device.
For instance, I have a Blue seas USB plug like this:
https://www.bluesea.com/products/1016/Dual_USB_Charger_Socket
When I plug the meter into this it reads 5.18 volts. When I plug my depleted phone into this meter, it reads 5.18 volts and 0.97 amps
When I used the USB cable from my Turcom Bluetooth speaker on my phone, no more than 0.47 amps
The Turcom Speaker itself never exceeds 0.42 amps even with my Samsung phone cable.
I have 2 other USB outlets, One behind my dashboard for driving, and one for over my Bed, that plug into a ciggy receptacle. Same make and model.
The USB outlet for my bed outputs 5.12v, unloaded, but when I plug my phone in, it drops to 4.89v, and current cannot exceed 0.81 amps. It tries to bounce upto 0.97 amps but when it does, the voltage drops to 4.7x, then the current drops, and it gives up trying to extract more than 0.81 amps at 4.89V.
The USB outlet by my drivers seat does much better, it can maintain 4.95 volts when loaded at 0.97 amps from my depleted phone.
All three USB plugs are rated at 2.1 amps per outlet, but I believe the two ciggy receptacle ones could NOT handle a 2.1 amp load. I have never measured the time it takes to fully charge my phone battery, but it is obvious the one USB supply over my bed is slower. I am not sure how this effects overall battery capacity, but will look into it. My phone has likely spent the most time plugged into this USB source, and I am not impressed with the battery life. In fact I just bought a new phone battery for 10$ and the phone is likely a year old and perhaps less.
If I were to drain the phone battery dead, and turn it off, and plug it into the meter to charge, it would say how much Mah it took to recharge the phone, and I could compare this to the 1800mAh rating of the battery and determine the remaining capacity.
My Lead acid battery voltage has had no effect on voltage output of Any USB source I've yet tested. 15.3 or 12.1, the USb source is 5.18 to 5.12V unloaded.
When My phone is fully charged, any current the meter shows, is what the phone is consuming just to Ping the cell towers and whatever else smart phones do. Often it is 0.00a but will jump to 0.08a for a bit, and other times to 0.24a, and more rare 0.51 for brief periods. And when the screen is on with a few more apps open, one can see it consume even more current.
This USB power meter stores some memory for the consumption of 10 different devices. There is only one button and this memory interface is Clunky, and I can't say I have yet mastered it, and I don't really care to as of yet.
Here is a professional review on the product:
http://lygte-info.dk/review/USBmeter KCX-017 UK.html
I think it is a neat device and I am glad i now own it. Thought I'd share.
I know many of you tablet owners use a lot more USB power than myself. I've never considered my USB devices as having much impact on my leadacid battery capacity or state of charge, but now with a little math, I could figure it out accurately.
But I hate math.
Many of you wonder how much your USB devices consume.
Wonder no more!
http://www.amazon.com/Jelly-Comb-Un..._sim_hi_3?ie=UTF8&refRID=0J6JSC47VP70W55RRM2X
It is an Amp hour counter too so one can see how much it consumes over a given period of time.
However one must remember the Mah figure is at 5 volts, and is not representative of the AH figure as if it were at 12 volts, but figuring in conversion inefficiencies, one might get away with doubling the Mah figures. 1000 Mah =1AH if the voltage is the same.
What i have found interesting with the product, it the output voltages of various USB power supplies, and how it affects the charging of the device.
For instance, I have a Blue seas USB plug like this:
https://www.bluesea.com/products/1016/Dual_USB_Charger_Socket
When I plug the meter into this it reads 5.18 volts. When I plug my depleted phone into this meter, it reads 5.18 volts and 0.97 amps
When I used the USB cable from my Turcom Bluetooth speaker on my phone, no more than 0.47 amps
The Turcom Speaker itself never exceeds 0.42 amps even with my Samsung phone cable.
I have 2 other USB outlets, One behind my dashboard for driving, and one for over my Bed, that plug into a ciggy receptacle. Same make and model.
The USB outlet for my bed outputs 5.12v, unloaded, but when I plug my phone in, it drops to 4.89v, and current cannot exceed 0.81 amps. It tries to bounce upto 0.97 amps but when it does, the voltage drops to 4.7x, then the current drops, and it gives up trying to extract more than 0.81 amps at 4.89V.
The USB outlet by my drivers seat does much better, it can maintain 4.95 volts when loaded at 0.97 amps from my depleted phone.
All three USB plugs are rated at 2.1 amps per outlet, but I believe the two ciggy receptacle ones could NOT handle a 2.1 amp load. I have never measured the time it takes to fully charge my phone battery, but it is obvious the one USB supply over my bed is slower. I am not sure how this effects overall battery capacity, but will look into it. My phone has likely spent the most time plugged into this USB source, and I am not impressed with the battery life. In fact I just bought a new phone battery for 10$ and the phone is likely a year old and perhaps less.
If I were to drain the phone battery dead, and turn it off, and plug it into the meter to charge, it would say how much Mah it took to recharge the phone, and I could compare this to the 1800mAh rating of the battery and determine the remaining capacity.
My Lead acid battery voltage has had no effect on voltage output of Any USB source I've yet tested. 15.3 or 12.1, the USb source is 5.18 to 5.12V unloaded.
When My phone is fully charged, any current the meter shows, is what the phone is consuming just to Ping the cell towers and whatever else smart phones do. Often it is 0.00a but will jump to 0.08a for a bit, and other times to 0.24a, and more rare 0.51 for brief periods. And when the screen is on with a few more apps open, one can see it consume even more current.
This USB power meter stores some memory for the consumption of 10 different devices. There is only one button and this memory interface is Clunky, and I can't say I have yet mastered it, and I don't really care to as of yet.
Here is a professional review on the product:
http://lygte-info.dk/review/USBmeter KCX-017 UK.html
I think it is a neat device and I am glad i now own it. Thought I'd share.
I know many of you tablet owners use a lot more USB power than myself. I've never considered my USB devices as having much impact on my leadacid battery capacity or state of charge, but now with a little math, I could figure it out accurately.
But I hate math.
