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Calling all Electrically inclined nerds!

Posted: Mon Oct 20, 2014 7:01 am
by RDClaes
I'm not sure I can clarify my question to one single concise sentence. Please see the paragraph below in bold.

I can't figure something out and when I asked myself where I had the best collection of tech savvy nerds that scare me with how smart they are TBT immediately came to mind!

Help me Brothers!

I have an FZ-G1 that I use for my everyday computer. I have it plugged into a FZ-VEBG11U desktop dock. I also have an Orico A3H10 10 port powered USB HUB

http://www.amazon.com/Super-Speed-Switc ... op?ie=UTF8.

When I dock my tablet it is telling me I don't have enough USB Controller hosts. A quick google shows pretty compelling evidence that the issue is the amount of power available to my USB hub.

The dock I have is powered as well as the USB hub (everything is powered).

My ultimate question is power related. When I bought the 10 port HUB I specifically bought it because it was supposed to be a higher powered device with 4A of power. I look at the power adapter and it specifies

Input:
100-240VAC
50/60Hz
1A

Output:
12V
3000mA

First off, if it has 1A input how does it output 3000mA? Isn't 3000mA 3A's? I know more about electricity than most people but far less than most electrically educated people. My understanding of Ohm's law would tell me that if I were to change the Voltage and resistance I could change the amperage. I see the output Volts is 12 from 100-240V and I'd have to assume the unit has step down converters to achieve this, thus changing the Ohm's (not particularly mentioned anywhere). Does this work out correctly?

The 2nd part of the question has to do with the power distribution. My common sense tells me that if I have a 10 port hub with 4A's of power (allegedly) it would distribute the power to the ports that ask for the most or evenly distribute it.


There are also 4 port USB 3.0 Hubs with the same 4A of power. Wouldn't the additional 6 ports be "weaker" if the power is the same? I cannot seem to find a 7-10 port USB 3.0 HUB that advertises more than 4A's. Is there a limitation I don't know about?

Thanks!

Re: Calling all Electrically inclined nerds!

Posted: Mon Oct 20, 2014 7:23 am
by Shawn
3000ma is 3A

First thing to remember is Chinese mfg labels tend to LIE.

USB ports are 5v....What's the amps at 5v?

Cheaper power supplies have greater losses which reduces the output.

The higher draw items will pull the most current..It won't be distributed evenly.

10 port hub .....4A total simple math gives 400ma per port....that's not much.

What are you running that needs so much current?

Re: Calling all Electrically inclined nerds!

Posted: Tue Oct 21, 2014 12:50 pm
by RDClaes
I'm not really using anything too crazy. I mean it is but it is all powered.

I have a USB optical drive that is not powered, a small USB receiver for my wireless keyboard / mouse.

Other than that the only things plugged in USB are monitors with USB adapter cables (VGA). Each monitor is powered except for one that is drawing it's power directly from the ports on the desktop dock.

I think I may just need to limit myself to a couple 4 Port guys so I can have a full amp per port.

I bought what was supposed to be a super high quality hub. I definitely did not cheap out haha.

Re: Calling all Electrically inclined nerds!

Posted: Tue Oct 21, 2014 1:52 pm
by Shawn
You could either return that one ..or..get a better power supply for it.

Is the inlet port the same as a Toughbook? 5.5mm

Re: Calling all Electrically inclined nerds!

Posted: Tue Oct 21, 2014 2:45 pm
by Rob
Claes,

I just checked and my adapter is IDENTICAL to yours.

1A at 120V = 120 watts.
3A at 12V = 36 watts, which is less.

It should be fine.

Thanks!

P.S, Jeff Daniels knows all about electricity! He also doesn't need any of this futuristic crap! :D

Re: Calling all Electrically inclined nerds!

Posted: Mon Oct 27, 2014 11:17 am
by RDClaes
I did buy a new one. This one has a 48W power supply and 10 ports that can be powered on or off in groups of 3. 1 extra at the end with a 2.1A charge for an ipad.

5 total things being plugged into the hub.
-1 External laptop DVD burner
-2 VGA to usb adapters
-1 Microsoct keyboard / mouse wireless adapter
-1 logitech USB keyboard / mouse wireless adapter

I've found if I have anything plugged into the G1 USB while I use the hub I get the controller error message.

If I plug everything in and then plug in the logitec USB adapter it does not give me the USB controller error but it simply does not work / do anything.

I've read up that the USB receivers for wireless tech are recommended to be on USB 2.0 and not 3.0. Not sure why that matters.

I have also not tried to daisy chain connect the 2 hubs I now have.

Re: Calling all Electrically inclined nerds!

Posted: Mon Oct 27, 2014 2:15 pm
by SHEEPMAN!
The most important thing to remember when running on solar power is don't plug anything in. Makes the batteries last longer. :rolleyes:

So I looked it up......read about the wire.....http://www.poweredusb.org/whatispusb.html .....namely 1.1 v.s 2.0....it was interesting. As is the part re: ground contact first to prevent arcing degradation.
Recipe:
With everything unplugged boot to a live linux os.
From terminal

Code: Select all

 lsusb #to see usb devices
Then start plugging in devices one at a time and running

Code: Select all

lsusb
Continue until something breaks.

Code: Select all

 dmesg | tail # shows the last ten things that occurred
Reminder: terminal does not read information after the[#]

FWIW