Power from RJ45 Jack

[benjampm]

Does anyone know how much power can be supplied from the Controller RJ45? I'm currently using it to power my mini director/FM transmitter. But I'm wondering if I can connect a wireless relay box to the 5V or 9v output on the mini director. The mini director states the 5v output is limited to 250mA but says the 9V output is limited based on the power input coming in. I'm assuming that means the power available on the RJ45 input coming from the controller. Anyone else used their mini director to power another device besides the FM transmitter?

[k6ccc]

It's not a lot.  Sorry, I don't have a better answer.

 

[rmturner54]

Agree with k6ccc. IMO, I would not chance a controller board for that.

[Steven]

I would test it. The 9v on the LOR network is supplied through an LM7809 linear voltage regulator, which has a 1.5A limit. The current won't get near this, and the regulator also has internal thermal overload and short-circuit protection. Not only that, but it's inexpensive and fairly easy to replace.

Unless your RJ45 is already corroded, it's not going to get near enough current to overhead and damage it. In my display I run DMX along with +12V through RJ45 jacks to (small) floodlights and RGB ribbons and have had no issues. (Albeit I do run 3 pins in parallel.)

The most likely cause of failure would be that the voltage drop along the cat5 cable reduces the voltage to a level too low to run your mini director. In this case the result would be that the director working intermittently or resetting. It would not cause permanent damage.

Another source of failure is that over a period of a couple of minutes, the temperature of the LM7809 (which doesn't have a heat sink) would rise to the point of shutdown. Again, this would not result in permanent failure as it would reset when the load is removed and it cools down.

So, to repeat: Just test it. It may not work but it's not going to cause any permanent damage.