Believe it or not this is a pretty popular
question. With all the different types of interfaces (Serial, Parallel, 10Base-T, 100Base-T, USB,
IEEE-1394 FireWire, IEEE-1284 Parallel)
it gets pretty crazy so lets see if we can make it a little easier on
you.
| Serial: | To determine the maximum length, some
will say that the total capacitance cannot exceed 2500 pF. Every cable has a
"capacitance per foot" rating (Click here to see the
capacitance per foot on our common wires). In order to determine the total
capacitance, just take the capacitance per foot and multiply it by the length
in feet. Or to determine the maximum length on a cable, take 2500 and divide it
by the capacitance per foot. For example, if you have a wire that's 15 pF/Ft,
and made a 150 foot cable with it. The total capacitance is 15 pF/Ft times 150
feet or 2250 pF, still within the limit. On the other hand, you want to
determine the maximum length of this 15 pF/Ft wire, take 2500 and divide it by
15 to get 167 feet as the maximum length.| Examples | | 15 pF/Ft x
150 feet = 2250 pF | | 2500 pF (max.) ÷ 15 pF/Ft = 167 feet
(max.) |
To see our list of serial products, click one
of the following categories: | | 10Base-T or 100Base-T: | The total length of wire
segments between a PC and a hub or between two PC's cannot exceed 100 Meters
(328 feet or about the length of a football field). To see a list of our
networking products, click one of the following categories: 10Base-T and 100Base-T, NIC, Repeaters, Hubs, Switches, Print servers,
Transceivers, or Converters. | | IEEE-1284 Parallel: | With the older style
"Centronics" parallel, the length limit is typically 9 to 12 feet although some
30 foot connections have worked. The IEEE-1284 can go up to 50 feet in length.
To see a list of our parallel products, click one of the following categories:
Parallel, IEEE-1284.Converters, Extenders, IEEE-1284
Auto switch boxes, Parallel Auto switch
boxes. | | USB: | In
practice, the USB specification limits the length of a cable between full speed
devices to 5 meters (a little under 16 feet 5 inches). For a low speed device
the limit is 3 meters (9 feet 10 inches). most manufacturers do not recommend
and will not support cables longer than 10 feet, although there are active
extensions available that will allow 16 feet runs and will daisy chain to give
you A total of 80 feet ADP31802-16, or
extenders that will allow you to have a USB Run 150' over Cat 5 cable, ADP3184. To see our
manual switches for USB Click
Here | | IEEE-1394
FireWire: | FireWire cables use 28 AWG wire and are limited to 4.5
meters maximum cable length. To see a list of our FireWire products, click one
of the following categories: FireWire Converters, PCMCIA card
and Hubs |
Cable Capacitance Guide
|
![[ Search ]](https://www.connectworld.net/iec/images/search.gif)
![[ Products ]](https://www.connectworld.net/iec/images/browse.gif)
![[ Browse by Connector ]](https://www.connectworld.net/iec/images/browse-by-connector.gif)
