Furuno MCU-002 Manual page 14

PoE Hub Requirement (if not using the supplied POE injector)
A PoE hub for the MCU-005 should be compatible with Alternative A (Type A).
PoE stands for Power over Ethernet. In additon to data comunication, power is supplied through an Ethernet cable.
Power feeding of PoE has two (2) types: Alternative A (Type A) or Alternative B (Type B).
Alternative A (Type A):
Alternative A is also described as Type A. While pins #1/2/3/6 of Ethernet cable are used for data communications,
the same pins are used to feed the power to a connected device. The MCU-005 is compatible with this type.
E.g.
Manufacturer : NETGEAR
Model : GS108PE
URL: https://www.netgear.com/business/products/switches/web-managed/GS108PE.aspx#tab-techspecs
Alternative B (Type B):
Alternative B is also described as Type B. While pins #1/3/4/6 of Ethernet cable are used for data communications, the
other pins #4/5/7/8 are used to feed the power to a connected device. The MCU-005 is NOT compatible with this type.
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