LinkPower
LPS1000 Adjustable Voltage PoE Switch
Page 46 of 71
2.8 PoE Injector and Cable Length Consideration
It is recommended to check the PoE equipment PoE cable length specification prior to
installation to ensure correct power is delivered to the PoE equipment. Using the wrong
voltage and/or exceeding PoE cable length may lower the products performance or in most
cases damage the product. When making your PoE cables, please adhere to TIA/EIA 568B
telecommunication cabling standard.
Ethernet network cables utilize pins 1, 2, 3, and 6 of an 8-pin RJ-45 connector. Equivalent PoE
cables should be utilized for reliable operation. STP type cables should always be used in
high EMI environment to minimize noise and maximize performance.
Network Type
Cable Type
10Base-T
4 Pair UTP/STP Cat 3, 5e, 6 cable, EIA/TIA-568-B.2 100-ohm (up to 100m)
100Base-TX
4 Pair UTP/STP Cat. 5e, 6 cable, EIA/TIA-568-B.2 100-ohm (up to 100m)
10Base-T and 100Base-TX standard specifies the cable length support up to 100 meters or
330 feet. Power delivery on the other hand limits the cable length according to your PoE
device specification. When utilizing proprietary PoE power scheme, check the voltage
tolerance of your PoE equipment. When in doubt, use 3VDC voltage attenuation per 25
meter of Cat 3, 5, 5e, or 6 cables. Using longer cable than the PoE equipment specified limit
may cause PoE equipment instability. Contact your PoE equipment manufacture for cable
length specifications.
