Want to design my own pedalboard PoE injector – any information on Remotes' power consumption?

JanosB · January 29, 2020 at 8:13 PM

Hi everyone,

being an electrical engineer I'd like to design my own IEEE 802.3af mode A compliant PoE injector, which– unlike all ready-to-buy devices I found out there – should accept 9V input voltage so that it could be powered from my pedal power supply.

If my injector should be able to provide the whole 15.4W as the IEEE standard requires, this would require a 9V supply delivering more than 2000mA, which is quite a lot for a pedalboard power supply. However, I wouldn't be surprised if the actual power consumption of the Remote would be a lot lower, this is why I would consider to limit the power that can be delivered to a senseful level.

Now as externally measuring the power consumption of a device powered via PoE is not really trivial, my question is: Has anyone ever used the Remote with a professional PoE switch that monitors power consumption of the devices attached and could give me some more insight regarding the real power consumption of the Remote?

DamianGreda · February 3, 2020 at 6:41 PM

You can connect it to KPA directly and measure current on one of the ethernet wire. It uses normal 5V supply in this mode over a pair of ethernet wires.

DamianGreda · February 3, 2020 at 6:48 PM

JanosB so you dont need poe if your power supply is near the remote. Just inject 5v to the right pair of wires.

TubeTom · February 3, 2020 at 6:57 PM

Don't these standards (IEEE standard 802.3af-2003 and 802.3at-2009 mode A) use about 48 Voltage?

DamianGreda · February 3, 2020 at 7:23 PM

TubeTom yes. POE wil provide high voltage after some handshake and response. But some devices may be designet to take operational voltage (5V) for example from the unused pair of ethernet wires. The downside is that you have to use relative short ethernet cable to avoid voltage drop. I belive this is the case with remote. It uses 5 v when it is connected directly with KPA or it can use POE when it is avaliable only in mode A.

DamianGreda · February 3, 2020 at 7:28 PM

I do not reccomend this if you do not have some electronic skills. But with use of some brekout connector it is easier to inject 5v then building whole POE device, especially if the power source will be near remote. But better to stay on the safe side and use dedicated poe injector. Still don't get why not use POE near KPA since you still need ethernet cable from kpa to the remote.Unless you want to use some WIFI connection.