1 Copper

Maximum Hub Number Surpassed

Concept: 27 nos mouse to be connected to a computer, but only one mouse will be controlling Dell Optiplex 9020 at a time.

What i did: Computer's 2 Nos. of USB port connected to Extron USB- Cat6 extenders and at the other end 2x D-Link HUB-H7 (Powered USB Hub) connected to each receiver, so 4x H7 are connected in total.

Issue: Only first 3 ports are working in all H7 USB hub!

Confusion: If Laptop is connected in place of Dell Desktop, all the ports are working fine!

Looking forward your help to come out of this issue.

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7 Plutonium

RE: Maximum Hub Number Surpassed

You cant extend and hub and hub and extend.  Neither of the products you used are Dell and neither are supported here.  USB hubs are often built into equipment such as computers, keyboards, monitors, or printers. When such a device has many USB ports, they all usually stem from one or two internal USB hubs rather than each port having independent USB circuitry.  What you are doing is not supported and never will be.

Physically separate USB hubs come in a wide variety of form factors: from external boxes (looking similar to an Ethernet or network hub) connectible with a long cable, to small designs that can be directly plugged into a USB port (see the "compact design" picture). In the middle case, there are "short cable" hubs which typically use an integral 6-inch cable to slightly distance a small hub away from physical port congestion and of course increase the number of available ports.

There is a maxiumum number of units 128 but that is for all devices

including hubs.

So you can have an 8 port hub with 16 port hubs attached.

You cannot daisy chain infinitely and you cannot daisy chain passive hubs.

So an active Port has 500MA or 900MA depending on USB 2 or USB 3.

That means an active port power supply must have 500MA or 2.5 watts per port

or 4.5 watts per port for USB3.

2.5 X 128 = 320Watts.   At 5v thats 64 AMPS of power.

Typical 5 port USB 2 hub has 12.5 Watts typical or 25 watts for USB3 hub.

So thats 2.5 AMPS @ 5v for a 5 port hub and 5 Amps for a 5 port USB3 hub.

The Maximum you can daisy chain is 1 either passive or active.  The cat 5 extenders count as a hub.

You cant hub extenders into more hubs and fan out from there.

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