USB 'external' hard drives and DVD writers often do not have a normal power supply, but derive their power from one (and often two) USB ports. However, the amount of current drawn is almost never quoted (possibly because it exceeds the 500mA at 5V per USB socket maximum).
Does anyone know of a simple way of measuring the total current drawn by these devices? I really don't want to bodge together a USB connector and stick an Ammeter in series...
Thanks!
How to measure the current drawn by a USB device?
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- PlatinumLounger
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How to measure the current drawn by a USB device?
John Gray
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- SilverLounger
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Re: How to measure the current drawn by a USB device?
Use Device Manager and for each USB root hub see Properties | Power.
Joe
Joe
Joe
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Re: How to measure the current drawn by a USB device?
Have you tried the following?
- Open Control Panel > Device Manager.
- Expand Universal Serial Bus controllers.
- Right-click a USB hub and select Properties from the popup menu.
- Activate the Power tab.
- You should see the power consumption of attached devices.
- Repeat for the other hubs, if present.
- Open Control Panel > Device Manager.
- Expand Universal Serial Bus controllers.
- Right-click a USB hub and select Properties from the popup menu.
- Activate the Power tab.
- You should see the power consumption of attached devices.
- Repeat for the other hubs, if present.
Best wishes,
Hans
Hans
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- PlatinumLounger
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Re: How to measure the current drawn by a USB device?
Thanks, both, but as I reported elsewhere, I don't believe the results!
USB webcam: exactly 500 mA
USB WiFi finder and WiFi dongle: exactly 500 mA
USB Flash Drives, various sizes and manufacturers: one of exactly 100 mA or 200 mA
I'll have a look tomorrow at a 320 GB hard drive which is at work, and which is connected into two adjacent USB ports on a server...
USB webcam: exactly 500 mA
USB WiFi finder and WiFi dongle: exactly 500 mA
USB Flash Drives, various sizes and manufacturers: one of exactly 100 mA or 200 mA
I'll have a look tomorrow at a 320 GB hard drive which is at work, and which is connected into two adjacent USB ports on a server...
John Gray
"(or one of the team)" - how your hospital appointment letter indicates that you won't be seeing the Consultant...
"(or one of the team)" - how your hospital appointment letter indicates that you won't be seeing the Consultant...
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Re: How to measure the current drawn by a USB device?
I guess you'll have to ask Jezza to build something like USB Drawbox for you as a KTS project...
Best wishes,
Hans
Hans
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- 3StarLounger
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Re: How to measure the current drawn by a USB device?
I'm sure this project would capture his attention, especially once he reads the disclaimer on the website:HansV wrote:I guess you'll have to ask Jezza to build something like USB Drawbox for you as a KTS project...
- disclaimer: For extreme geeks only. This device description is for informational purposes only. Attempts to duplicate this could result in fire, personal injury, or destruction of expensive electronics. Do not attempt to duplicate this.
Samantha
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- PlatinumLounger
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Re: How to measure the current drawn by a USB device?
I'm not quite convinced of the intelligence/practicality of someone who builds the whole thing in a metal box...!HansV wrote:I guess you'll have to ask Jezza to build something like USB Drawbox for you as a KTS project...
And as far as I can see, it couldn't measure the current drawn by a double/Y plug for a hard drive or an optical drive?
John Gray
"(or one of the team)" - how your hospital appointment letter indicates that you won't be seeing the Consultant...
"(or one of the team)" - how your hospital appointment letter indicates that you won't be seeing the Consultant...
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Re: How to measure the current drawn by a USB device?
That's YOUR assignment for today...
Best wishes,
Hans
Hans
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- PlatinumLounger
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Re: How to measure the current drawn by a USB device?
The only commercial device I can find is the USB Port Voltage and Current Tester, but I can't find anything sold in the UK...
John Gray
"(or one of the team)" - how your hospital appointment letter indicates that you won't be seeing the Consultant...
"(or one of the team)" - how your hospital appointment letter indicates that you won't be seeing the Consultant...