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APPLICATION NOTES:

PoE for ROAMEO Access Points

ROAMEO is a wireless matrix system from RTS. In this Application Note, we will look at a way of connecting the 

ROAMEO Access Points using Power over Ethernet, PoE.

Power over Ethernet is a way of simplifying wiring for devices that connect to Ethernet. With PoE, there is no 

need for a separate power supply. There is an upper limit on the amount of power that can be supplied using 

PoE, and the limit is dependent on the type of PoE switch used. In general, PoE is intended for devices that 

require little power, up to about 13 Watts. (There is another standard called PoE Plus, which allows up to 25 

Watts of power, but we will not get into that here.) With PoE, the data signal is superimposed on the power. 

On the receiving end, filters are used to pick out the data from the power. When a PoE device is turned on, it 

communicates with the PoE switch to “negotiate” the right electrical parameters. For this reason, PoE devices 

can never be connected in cascade.

The ROAMEO Access Point, AP-1800, is designed to 

be tolerant to PoE, but it is not designed to use PoE 

directly. Expressed differently, it is PoE tolerant but 

not PoE enabled. RTS does supply a PoE adapter kit, to 

allow the AP-1800 to work with a PoE enabled switch. 

The PoE kit is shown in Figure 1.

The PoE adapter is designed to support three different 

voltages. The AP-1800 expects 12 V. The setting on the 

PoE adapter (TP-Link) must be set to 12 V before it is 

connected to the Access Point. This is shown in Figure 

2. To set it to 12 V, slide the little selector to the left. 

Note if the selector is in the wrong position, nothing will 

break. The AP simply will not power up.

The kit can be ordered as any other part. The part 

number is F.01U.335.167 (POE ADAPTER 12V) and it 

contains the following parts:

 

     • The PoE adapter

     • A barrel adapter

     • A short DC-cable

     • Two Ethernet-cables

Figure 1. The PoE kit for AP-1800

INTRODUCTION

Figure 2. The voltage selector should 

be in the left-most position for 12V

SETTING THE VOLTAGE ON THE PoE ADAPTER

WHAT IS PoE?

THE ROAMEO AP

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