Arduino relay power over Ethernet cable? Answered
Hi. I have an Arduino setup with 2 individual relay boards controlling two 240v power outlets. The relays are housed separately from the Arduino and I have connected the two via a standard ethernet cable. The relays I have are both 12v powered and switched via a 5v Arduino digital pin.
I have currently wired the following.
Orange and orange/white ---> 12v+ (from a 12v plug transformer)
Blue and blue/white ---> GROUND (connected to both plug transformer and Arduino GROUND)
Brown ---> Switched +5v from Arduino to relay 1.
Brown/white ---> Switched +5v from Arduino to relay 2.
One of these relays for some reason isn't working properly. The board is receiving the right power but the relay itself is not clicking/switching. Maybe sticky contacts. The whole thing is already wired and the unused cables of the network cable trimmed so I cannot use them.
I have a spare single 5v powered relay board which I could replace the faulty 12v with, but with no wires left to connect it, could I pinch one from the orange pair that I am sending 12v through to the first relay and use that for the 5v to the replacement one? In a less round about summary... can I send 12v+ through a single strand of ethernet cable with a run of only about 30cm?