TPS2373: Cable length limitation

chentsu chung

Mastermind 6180 points

Part Number: TPS2373

Hi,

Here are some question about PoE cable length:

1. What is the limitation of PoE cable? Only the voltage drop? Or anything else?

2. What kind of cable you recommend to use for length 100m application?

3. refer to question 2, is there any testing report about that? Or any sucessful case?

Thank you.

C.T.

over 6 years ago

0 Darwin Fernandez over 6 years ago

TI__Mastermind 41770 points

Hi Chentsu,

1. From a PoE PD controller prospective, yes because you have to be above the UVLO of the PD for the pass FET to turn ON. From a cable prospective, it is thermal (higher resistance) and data corruption at longer lengths.
2. IEEE802.3bt standard bases its specs around a CAT5e cable with a 100m length.
3. Please see refer to #2 answer, the IEEE committee uses CAT5e system.

I recommend looking at the white paper regarding the .bt standard shown in the below link. Thanks!
training.ti.com/power-over-ethernet-getting-started-new-standard

0 chentsu chung over 6 years ago in reply to Darwin Fernandez

Mastermind 6180 points

Hi Darwin,

Thanks for your help!

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TPS2373: Cable length limitation