C = how many Amps you have stored up (i.e. total Amp through put) it does not mean it charged that much in an hour, as this number will continue to get larger over 2 or 3 hours as long as your devise of multiple devices continue to accept a charge. P = how many Watts (or V * A ) have been stored up You could use these two values to record how many amps or watts of charge you are getting out of a small power bank (usually ratted around 10,000 MAH to 22,000 MAH). Because your phone may not be all the way discharged when you plug it in, this allows you to quantify how much charging you actually are getting over several consecutive charging sessions (if you record your numbers and add them up). I seriously doubt that I am getting 22 Amp hours of charging out of my phone bank when it barely charges my phone 3 times. So here's a way to test that.
A very useful video, so thanks for that. I think this meter is especially useful to check cables/wires from USB to phone. Some cables just cannot carry much current - esp el cheapo ones. These need to be tracked down and binned!
great video well done. I have two different types of these both Droks and crude measurements shows the device itself draws about 10mA to run. I would imagine the LEDs or the OLED display is using most of that.
'C' as used by DROK is NOT about the capacitance of capacitors or 'condensers' or the distributed capacitance of a circuit. DROK'S 'C' is amp hours as I explained earlier.
Should we look at voltage, amp or power for fastest charging speed for our phone? Could we just look at total power for more accurate measure of voltage and amp?
Would this not also be a way to test cables? Sometimes i use a charger that i know is good but with an old wire that i haven't used in a long time and it will charge really slow or the device will even tell you that it's charging slowly. If you know how much you phone usually draws with a good cable you should be able to compare wires, right?
Yes you can use this tool to check if the USB cable is good for charging. Easy way is to compare your aftermarket cable to the original factory cable by swapping the cable when charging the same phone and check the current draw.
Curious, how do I measure watt hours from a portable battery bank. I want to make sure I actually purchased a 266Wh battery and didn't get scammed. Thanks
Do you think it would be safe to use this device as a continuous usb power splitter? I am thinking to use this to split 1/2 usb ports on a power bank. Each port outputs 5v 3a, this device would split one of those ports to power 2 dash cams consuming 5v 1a each. Should be ok as it's not hitting the limit?
Your cap is mills amp like a iPhone has a 1600 milliamperes . Every 1000 milli amp you can charge 1 amp so if you have a 1600 you really can charge at 1.6 amp anything higher is not good for your battery. Hope this helped
+Mike65231 what the h are you saying? 1milliampere is 1 aampeere, it is like saying 1000g = 1kg, if you are charging at 1600milliampere you ARE charging at 1,6 ampere, saying you can charge higher or lower than 1,6ampere has no sense. Plus, the charge was fluctuating cause the display was on, many device act differently when drawing power when the display is on/off
One thing to remember is that you are comparing mAh at 3.7 volts in the pack with mAh on the output at 4.9 volts. For instance, a 10,000 mAh battery pack at 3.7 volts nominal is 37 watt hours. If you divide 37 by 4.9 volts, then you get 7,551 mAh. So, if you get 25% less amp hours than you expected, it is because of the voltage differences in the pack vs. outside the pack.
Good product. Product Description should include special meaning of 'C' = Capacity=Amp Hours NOT Amp/Hours. Instructions could reference an explanation for unusual use of symbol 'C' or outright explain that C or Capacity really means Amp Hours or Amps multiplied by Hours i.e. current * Time. Amp Hours * nominal volts = nominal watt hours i.e. energy supplied by the charger. Not all the supplied energy will be stored due to inefficiencies involving heat and chemistry.
One thing to remember is that you are comparing mAh at 3.7 volts in the pack with mAh on the output at 4.9 volts. For instance, a 10,000 mAh battery pack at 3.7 volts nominal is 37 watt hours. If you divide 37 by 4.9 volts, then you get 7,551 mAh. So, if you get 25% less amp hours than you expected, it is because of the voltage differences in the pack vs. outside the pack.
Capacitance is to ensure what you have connected does not exceed the USB specification, including the added capacitance of the USB cabling though that is usually quite small relative to capacitor(s) in the connected device. For example the inrush current can be excessive if you start daisy chaining unpowered hubs. It can blow your USB port circuit, or worse a subcircuit in a motherboard chipset. That's a bit obscure feature to place in the hands of the average hobbyist, but I imagine they went ahead and did it because the IC they used supported it so virtually no extra cost to do.
First of all that usb unit is not a testing unit....a real testing unit does not come that small...testing units usually come with software....I've purchased testing units and the best testing units all come with software...these units are meant to fail they are not accurate and do not last....and for 12$ what do you really expect.....
C = how many Amps you have stored up (i.e. total Amp through put)
it does not mean it charged that much in an hour, as this number will continue to get larger over 2 or 3 hours as long as your devise of multiple devices continue to accept a charge.
P = how many Watts (or V * A ) have been stored up
You could use these two values to record how many amps or watts of charge you are getting out of a small power bank (usually ratted around 10,000 MAH to 22,000 MAH).
Because your phone may not be all the way discharged when you plug it in, this allows you to quantify how much charging you actually are getting over several consecutive charging sessions (if you record your numbers and add them up). I seriously doubt that I am getting 22 Amp hours of charging out of my phone bank when it barely charges my phone 3 times. So here's a way to test that.
Great Video - This device is also useful for testing intermittent / damaged USB cables if you have a working cable to compare it to.
Thanks! I have one of these and came to find out what the "power" was actually measuring and now I know. I appreciate it.
+djsunproductions Thanks for your comment!
I think that’s the point of buying/owning one of these.
A very useful video, so thanks for that. I think this meter is especially useful to check cables/wires from USB to phone. Some cables just cannot carry much current - esp el cheapo ones. These need to be tracked down and binned!
Excellent instruction. I purchased same item based on your vid. Many thanks.
Thanks for the video.. is there anyway to make the device show the current and voltage straight away without showing the capacitance first?
No it won't do that
great video well done. I have two different types of these both Droks and crude measurements shows the device itself draws about 10mA to run. I would imagine the LEDs or the OLED display is using most of that.
Hi buddy. I just came across your video I was wondering if you would still recommend it
I'm using one right now. Made by Dragon-X. Works great.
Keep the display off , it usually splits the current power draw to prioritize charging.
Please elaborate
What is the difference between USB 2 and USB 3 for volts and amps ? I understand there is a HUGE difference in data transfer rate
'C' as used by DROK is NOT about the capacitance of capacitors or 'condensers' or the distributed capacitance of a circuit. DROK'S 'C' is amp hours as I explained earlier.
Should we look at voltage, amp or power for fastest charging speed for our phone? Could we just look at total power for more accurate measure of voltage and amp?
This video is sooo Awesome!! Very well done.... now I'm gonna buy one!!!
Would this not also be a way to test cables? Sometimes i use a charger that i know is good but with an old wire that i haven't used in a long time and it will charge really slow or the device will even tell you that it's charging slowly. If you know how much you phone usually draws with a good cable you should be able to compare wires, right?
Yes you can use this tool to check if the USB cable is good for charging. Easy way is to compare your aftermarket cable to the original factory cable by swapping the cable when charging the same phone and check the current draw.
Curious, how do I measure watt hours from a portable battery bank. I want to make sure I actually purchased a 266Wh battery and didn't get scammed. Thanks
What are the units for capacitance?
Very helpful, just bought but do not know how to use it. Thanks
Do you think it would be safe to use this device as a continuous usb power splitter? I am thinking to use this to split 1/2 usb ports on a power bank. Each port outputs 5v 3a, this device would split one of those ports to power 2 dash cams consuming 5v 1a each. Should be ok as it's not hitting the limit?
Thank you !! This video was very helpful
Great review, I'm getting one today.
Thank you and good info!
Super nice review. Thanks
how do you setup úsb meter to test amp output of laptop
Very helpful video. Very informative.
Your cap is mills amp like a iPhone has a 1600 milliamperes . Every 1000 milli amp you can charge 1 amp so if you have a 1600 you really can charge at 1.6 amp anything higher is not good for your battery. Hope this helped
+Mike65231 what the h are you saying? 1milliampere is 1 aampeere, it is like saying 1000g = 1kg, if you are charging at 1600milliampere you ARE charging at 1,6 ampere, saying you can charge higher or lower than 1,6ampere has no sense. Plus, the charge was fluctuating cause the display was on, many device act differently when drawing power when the display is on/off
1000 mA = 1 A
Maybe capacity of recharge batteries. lets you know if battery is losing charging capacity
One thing to remember is that you are comparing mAh at 3.7 volts in the pack with mAh on the output at 4.9 volts. For instance, a 10,000 mAh battery pack at 3.7 volts nominal is 37 watt hours. If you divide 37 by 4.9 volts, then you get 7,551 mAh. So, if you get 25% less amp hours than you expected, it is because of the voltage differences in the pack vs. outside the pack.
and losses due to inefficiencies reduces it by 10-20%
I have the kwesisi verson that the usb plug is not a cable so it’s more durable where as the cable could get chewed by a dog or cat
Good product. Product Description should include special meaning of 'C' = Capacity=Amp Hours NOT Amp/Hours. Instructions could reference an explanation for unusual use of symbol 'C' or outright explain that C or Capacity really means Amp Hours or Amps multiplied by Hours i.e. current * Time. Amp Hours * nominal volts = nominal watt hours i.e. energy supplied by the charger. Not all the supplied energy will be stored due to inefficiencies involving heat and chemistry.
will this tell me the voltage from the battery in my car.?. that's what I wanted...
+Jose Guido No
nice
battery capacity
One thing to remember is that you are comparing mAh at 3.7 volts in the pack with mAh on the output at 4.9 volts. For instance, a 10,000 mAh battery pack at 3.7 volts nominal is 37 watt hours. If you divide 37 by 4.9 volts, then you get 7,551 mAh. So, if you get 25% less amp hours than you expected, it is because of the voltage differences in the pack vs. outside the pack.
Capacitance is to ensure what you have connected does not exceed the USB specification, including the added capacitance of the USB cabling though that is usually quite small relative to capacitor(s) in the connected device. For example the inrush current can be excessive if you start daisy chaining unpowered hubs. It can blow your USB port circuit, or worse a subcircuit in a motherboard chipset.
That's a bit obscure feature to place in the hands of the average hobbyist, but I imagine they went ahead and did it because the IC they used supported it so virtually no extra cost to do.
so much fake junk on eBay
First of all that usb unit is not a testing unit....a real testing unit does not come that small...testing units usually come with software....I've purchased testing units and the best testing units all come with software...these units are meant to fail they are not accurate and do not last....and for 12$ what do you really expect.....
So I guess my Fluke 87 multimeter is not a testing device since it doesn't come with a software. I learn something new from UA-cam University.
You also can use a simple USB gadget:
www.ramser-elektro.at/lil-usb-tester-usb-schnittstelle-schnell-getestet/