Can ethernet cables be too short?

Velvis

Well-Known Member
Reaction score
44
Location
Medfield, MA
Im installing a new switch to a patch panel. To make it nice and neat I need about 1.5' cables. Saw some stuff online saying not to go below 3' but Amazon is selling a ton of cables shorter than 3'


Just wondering what the consensus is.
 
From switch to patch panel doesn’t matter as the cable goes beyond the panel out to the jack points, and then into a device, so would normally be plenty of cable between the switch and the port on the actual device.
It can be too short if going from a switch direct to a device though. Not sure what the minimum is though.
 
There is no minimum length for Ethernet cabling. I've personally made wires that were little more than two modular connectors end to end, they work fine. The max length of 100m still applies.
 
I frequently use lots of very short (0.3m/0.25m) patch cables in equipment racks as uplinks between switches and firewall/routers, as well as to/from patch panels. Never had any issues. I prefer keep the cables as short as possible.
 
Yeah, definitely no "too short" limit for ethernet to work. Not even device to device. The electrical resistance difference between a 1-inch cable and a 10-foot cable is virtually immeasurable. It's not until you get to that 100m mark that the resistance of the wire starts to add up and cause potential issues.

That having been said, I've seen it work at 150-200m with a quality switch and some CAT6 cable (which is heavier gauge wires). Certainly not the recommended way, but for that occasional piece of equipment on the far side of a big factory it's worth trying first and adding a switch in the middle only if necessary.
 
As long as we are talking twisted pair and an impedance of 100MHz, there is no published minimum length. Maximum length is 100 meters/328 feet due to the signals timing.
 
I routinely buy and use 1ft patch cables all the time never had a problem

Sent from my SM-G870W using Tapatalk
 
From this page - http://www.ossmann.com/5-in-1.html

loopback.jpeg
 
I can't believe he complains about having to carry a couple different cables.

Sent from my SM-G870W using Tapatalk
 
At home, I have an ethernet cable with a length of 50 centimeters between the switch and a device. No problems at gigabit speed. on a customer's patch panel cables with the same length were used between patch panel and switch. Also no problems. jfyi.
 
Back
Top