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Question: I want this to run 4 external hard drives that are self powered (usb powered)  Will this hub work for that application?
Document: I have an iMac, which only has 4 USB ports, but want to connect lots of peripherals to it, without constantly unplugging them. I've tried many usb hubs, but I couldn't find a good one that allowed me to sync my iOS devices, or use USB-powered portable hard drives. The Plugable USB 2.0 10 Port Hub is exactly what I wanted.
switching power supply coming through a mini usb connector. Look at the size of those contacts and use your brain. Your USB hub is for transfering data, not for arc welding. Sensibly, since it takes some power to run the hub, and you have 10 ports available, you do not want to load down the wiring with more than 3 or 4 power drawing devices, especially ones that have a horrible start up current, such as disk drives.
This is a great product for anyone who doesn't have enough usb ports. I have 4 external hard drives attached to it and at any given time work within each one. Speed works just as if I was attached to the computer directly!
This is a great power usb hub, and just what I needed. Been using it for two weeks now and it's been a great addition to work station. I love the fact that it has so many plug ins. I have 3 external hard drives, a wacom art tablet, a card reader, a usb powered laptop base, a Magic Jack, and a flash drive. I was having to constantly juggle usb space and now everything is plugged in and ready for fast use! Hurrah!
Plugable's USB 2.0 10 Port Powered Hub filled the bill for my MacBook needs, allowing me to hang several external hard drives and a wireless mouse wart on the hub, while leaving the second USB port on the laptop open for flash drives. Since the hub itself is self-powered, the drain on the MacBook USB ports is minimized.
Arrived much sooner than I thought with great packaging. It installed its self and started work almost at once. I plugged in my 2 external hard drives and they ran with no problem. Also ran the the Wacom tablet off of it. So far no problems.
I have 3 external Hard Drives plugged into this hub along with my camera USB and Apple USB transfer cord for our iPads. This hub just works and works perfectly which is what you want out of a hub.Apple MacBooks only have 2 usb ports (One of which is taken up by my wireless mouse/External keyboard USB dongle) so this hub is a godsend and the fact it works so well really makes it worth every penny I paid for it.
I had a usb hub that I thought would look and work great, but I was sad to find that it wouldn't power my usb items enough to let them run. This included my flash drives and external drives. When this item came in, I was very impressed by its beauty. Super shiny smooth black finish with its own power supply. I hooked it up and it started to glow blue on the outlines and down the center! Matches my PC perfectly.
The Plugable 10-port USB2.0 hub is extremely handy for a gadget pack-rat like me. I now have a way to use all of my external hard disks, pen drives and iPods at the same time. The best part is that all devices are actually powered by the hub, so your laptop battery won't run out as quickly. The swiveling ports are a neat touch and I find them handy for USB pen drives.All in all, I'm extremely happy with this device.
I have been looking for a USB 2.0 hub that could reliably sync/charge my iPhone and run a few external hard drives. I hate plugging my iPhone in and having all the drives disconnect and sometimes reconnect. That has happened with every other powered hub I have used. But not this one. I have my iPhone and 2 flash drives on one side and 2 external TB drives on the other side. No problems. I have found that the two sides are like separate hubs.
Answer: MANUFACTURER ANSWER: Thank you for posting your question. External drives tend to be extremely power hungry because they have motors along with their electronic circuitry. They usually draw the maximum current that is allowed from a USB 2.0 port (500mA) or even more. Because of this, I would not recommend running four USB-powered external drives from this hub. It is designed for a typical mix of USB devices, such as a keyboard, mouse, flash drive, etc., including an external drive or two. The AC adapter for the hub supplies a maximum of 2.5 amps, so if the four external drives you mentioned each drew 500mA, then that alone would put the AC adapter near its capacity. Because external drives often draw more than the specified limit, especially when starting up, I would be concerned that a drive might disconnect suddenly due to lack of power during a write operation, possibly corrupting data on the disk. To be safe, I would recommend a maximum of three external drives if they were by themselves, or two if other devices are attached to the hub. For using more drives, I recommend our 7-port USB 2.0 hub with a 3.0 amp power supply (http://plugable.com/products/USB2-HUB-AG7) or one of our USB 3.0 hubs (which work on USB 2.0 ports), with 4.0 amp adapters. I hope this answers your question. David, Plugable Support