User Manual

Installation
Power over Ethernet (PoE) PoE
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9.4 Power over Ethernet (PoE) PoE
Principle: "Usable signal and power supply on the same cable".
Benefits
Power over Ethernet (PoE) is a simpler solution to supply power to low consumption room operator units. It
saves on power cables and associated installation costs. PoE can be used to connect Ethernet devices in
difficult to access locations or areas where multiple cables are disruptive.
* Power voltage and current is based on the PoE switch used as well as the number of connected touch panels.
Function
On PoE, Powered Devices (PDs, here: End units) are supplied by Power Sourcing Equipment (PSEs). The
voltage is supplied over the RJ45 plug and twisted pair cable (TP), and by device over:
● Wires that also transmit data
● Unused wires on the RJ45 connection
PoE topologies
PoE requires a star topology. Typical PoE switches have 4 to 16 outputs.
As a result, multiple switches are used in a line topology on larger systems (e.g. suites in a hotel).
Additional topologies:
● Certain switches (general industrial types) possess an uplink, i.e. multiple switches can be switched in
series.
● An individual consumer can be powered using a PoE injector. This is an intermediate power source (mid
span), in contrast to direct power by the PoE switch (end span).
PoE switches / injectors
● Use only switched design for industrial use
● Transmission speed: 100 Mbps
● Compliant with IEEE 802.3at
● Power class 4 (12,95-25,50 W)
● Type 2
● The switches must support supply alternative A