ctgoldwing
Getting comfortable
I have a PTZ that was 'temporarily' installed on a tree in the woods a few months ago. My purpose was to try & video the various critters that wander through. Its been a lot of fun and although I haven't snagged the bear or bobcat that are known to be in the neighborhood I have clips almost every day of the deer and foxes as well as the occasional flying squirrel, opossum, raccoon and owl. I had planned on a more permanent installation with an additional 2 or 3 fixed cameras, all POE.
The issue I soon discovered was the equivalent of 'red eye' in flash photography - 'white eye' from the IR in the camera. Looks like the White Walkers are making a comeback. Easy solution, just add some IR off camera. That bought me to the next problem, Mr Ohm's Law.
I had already built a 12 volt supply package mounted in the basement. A quick load analysis of what I think will end of in the woods came to 8 amps at 12 volts. Roughly a third will be at the 1st existing camera area approximately a 30m run. The additional future cameras & IR sources will be at least another 30m beyond that. 14ga copper wire is way too small (~4 volt drop in 30m). Even 10ga is too small. The resistance in the wire is too great. So on to plan B.
Plan B - A 48 volt 10A DC power supply is small and inexpensive. An inverter that takes 36-48V and converts it to 12V is also small and inexpensive. The bonus is the 12V inverter is made for golf cart use so its sealed and weatherproof. Problem is now solved. Using a 48 volt supply effectively reduces the current by ~75% and the resulting voltage drop. Because the inverter can accept 36-48V input the voltage drop in the 48 volt line really becomes a non-issue. So I mount a 48V supply inside the basement and run 30m of 14ga wire to a plastic box with the inverter mounted on the outside of the box. All the wiring connections are inside the weatherproof box. I also ran 'sense wires' back so I could monitor the actual voltages at the camera site.
We had some abnormally warm weather in January so I was able to make a small trench for the 1" pvc pipe across the lawn. As soon as I reached the woods area I left the pipe exposed on grade. Note to self - abnormally warm weather in CT in January doesn't last long. The rest of the project outside took place in really cold temperatures
FWIW here are some images of the project. Note: the extra wire hanging above the plastic box in the finished photo is for powering the IR illuminators which will be placed above the camera.
The issue I soon discovered was the equivalent of 'red eye' in flash photography - 'white eye' from the IR in the camera. Looks like the White Walkers are making a comeback. Easy solution, just add some IR off camera. That bought me to the next problem, Mr Ohm's Law.
I had already built a 12 volt supply package mounted in the basement. A quick load analysis of what I think will end of in the woods came to 8 amps at 12 volts. Roughly a third will be at the 1st existing camera area approximately a 30m run. The additional future cameras & IR sources will be at least another 30m beyond that. 14ga copper wire is way too small (~4 volt drop in 30m). Even 10ga is too small. The resistance in the wire is too great. So on to plan B.
Plan B - A 48 volt 10A DC power supply is small and inexpensive. An inverter that takes 36-48V and converts it to 12V is also small and inexpensive. The bonus is the 12V inverter is made for golf cart use so its sealed and weatherproof. Problem is now solved. Using a 48 volt supply effectively reduces the current by ~75% and the resulting voltage drop. Because the inverter can accept 36-48V input the voltage drop in the 48 volt line really becomes a non-issue. So I mount a 48V supply inside the basement and run 30m of 14ga wire to a plastic box with the inverter mounted on the outside of the box. All the wiring connections are inside the weatherproof box. I also ran 'sense wires' back so I could monitor the actual voltages at the camera site.
We had some abnormally warm weather in January so I was able to make a small trench for the 1" pvc pipe across the lawn. As soon as I reached the woods area I left the pipe exposed on grade. Note to self - abnormally warm weather in CT in January doesn't last long. The rest of the project outside took place in really cold temperatures
FWIW here are some images of the project. Note: the extra wire hanging above the plastic box in the finished photo is for powering the IR illuminators which will be placed above the camera.
