I wish to run a nodemcu at the back of my garden to do a variety of tasks, its about 30 meters from the nearest power point, what would be the ideal way to power this over such a distance?
My wifi works fine at this location so its only power I need to supply to the unit.
My (unsuccessful) experiments so far:
I have enough of CAT5 network cable laying around so thought I would experiment with that, not sure what current it can carry though…?
I tried a 2A 5v Power supply patched to 2 pins of the CAT5, at the destination it patches to the power pins of a micro USB cable. This works over short lengths but not over the 30 meters, voltage at nodemcu was 1.5v
So I tried using a 12v 1.5A plug pack going to CAT5, at the destination I added a little 12v-5v regulator (LM78H05 and a couple of caps) to micro USB cable but nodemcu light was very dim. Power level measured 4v going in so I figured still too much drop over the cable run…
So I tried using a 19v 5A old laptop PSU going to CAT5, at the destination same regulator (I checked level going in which had dropped to 12v over the cable length so figured this would be ok)
This seemed to kill my nodemcu ? Powers it fine but non-responsive to data and if I try to reprogram it direct from pc it cant be detected. Not sure why, it had a perfect 5v level good going into the nodemcu…
Solar panel & battery? Several projects out there for this. If you are using only for sensors & not actuators, you could even have the nodemcu go to sleep until it is time to take and send a reading to HASS, saving even more battery power.
I think you need to be careful about using the cat 5 cable - you are playing with POE that has its standards for a reason. How happy are you with moisture shielding on that cat 5 cable if it runs across the garden?
Use all the pairs of the cat 5 (I assume you aren’t carrying the network connection, just using the cable for power only).
EDIT: but really if you want something that far from power, use some battery compatible hardware, like mysensors or something. Anything wifi will chew through battery unless it sleeps most of the time.
I have a wemos D1 mini mounted on the wall, three floors down from my apartment, I send power down through old coax cable that runs through the walls, theres about 30m of it, I send 12v in and at the far end use a 12v>5v regulator and this works fine for me.
maybe try using more pairs of wire ? so 4 pairs each for + and - ?
Use an AC - AC transformer at the power source to covert it to 24 volts or whatever, and then run that across the cat5 line, and then convert to DC and drop the voltage again near the nodemcu. AC current can run further distances with much less power drop than DC current.