Do I need a device connected to have a reading? I to test the max amp output of a usb, before connecting anything, any recomendations if negative?
1767527
The max output of a usb will widely vary depending on what you attach to it. If you are using this to just measure output from a non-usb thing, this meter may not work at all. For example, if I use a special charging cable that is not a data cable, this meter does not work.
1767528
Yes, you need a device connected to have an ampere reading. Otherwise, the screen would simply display zero. If you have an engineer friend, ask him to make a simple circuit that could handle a 3 amp load (good enough for this amp meter).
1767529
You can't test the "max amps" of something without a load testing that max amps. Amps is "flow", volts is "pressure", so while you can always use a pressure gauge on a water line, the only reason a flow meter would exist is if that water's flowing somewhere. :)
1767530
To measure current there needs to be a load on the circuit. With no load there is no current. When a circuit is designed such as a SUB port it is made to handle a set max current output that means that a load put on it should not exceed that amount or the port will burn out. If you are building your own devices to power off a SUB port you should put a fuse in line rated at the maximum current output of that port.
401052
Make sure you have the USB driver fully up to date and if you are using a USB hub that is have enough power for it.
824205
Using the correct USB port, the NT90C should be able to read the number of connected electronic devices and output 5V/2.1 (max) to the device that is connected. Charge cables with no device connected to the NT90C will have no effect to the max output.
334589
Unit does have a usb input. I have not tried to use it, but it should work.
1389839
Absolutely not. The amplifier needs 12 volts at 2 amps or more. A USB port supplies 5 Volts and only 1/10 to 1/2 amp at best. The new USB port standard (3.1 - yet to be released) will supply much higher current, but it's still only 5 volts. Besides, the plugs and sockets don't match up anyway.
1574416
Sorry. Don't know this answer. I am not for sure what this would actually matter in this case as you hook this up thru USB.
1862672
There is no USB power input on this unit. Power is supplied and the internal battery charged by the supplies power supply/plug. If your USB Battery had the appropriate plug adapter, I could see that working though. Hope this helps.
2096027
No, you need the USB. But if you have something that could connect the USB to a outlet you can go that.
449907
This will only work with a standard serial device. There is no connection for USB.
893166
Does the digital reading show you a full charge? Is whatever you are plugging in drawing too many amps?
330363
Sure, as long as your USB supplies 5V power, which most USB do, it is worth a try, as its only taking power, it wont work if there is no power, and there wont be any damages which I encountered, though you try at your risk.
298294
No, only through the hdmi cable. You have to buy a special cord 30 pin to hdmi and a mini hdmi adapter. The usb only works for a storage device reader.
706763
I think it's restricted to 2.4 amps per port, however, this should not be an issue, no device that charges using USB pulls 4 amps
1489206
Seems to work well when connected to a regular USB port. So far I have not confirmed that any of the USB ports I have used are USB2. I apologize for that. Good luck with finding a definate answer.
1026162
You must to read a little amount more than 1.5 or 9 volts. For example you can read 1.523 volts but if you read 1.42 the device is over
753489
That depends on the USB reader and how your bios sees the reader and attached drives. Check your bios first.
1456222
It is not listed on the device. wikipedia says "Powered USB is a proprietary extension that adds four additional pins supplying up to 6 A at either 5 V, 12 V, or 24 V." I have a 5V 2 Amp adapter whose connector is too small.Output of the cable reads 5 V. I had to check because I had not heard of 12 V or 24 V in conjunction to USB.