# Running a power and Ethernet extension

I want to install a pseudo temporary security camera to the far corner of my yard to watch the bird feeders. Can I run an Ethernet cable and an electrical line (both outdoor and water rated) through the same conduit? The Ethernet cable will not serve POE. I also plan on leaving the conduit above ground, except across a 10’ yard area walkway.

Is the power circuit low voltage? If so, you are good. If the power is not low voltage per the NEC, any low voltage wiring in the same conduit must have a 600V or higher insulation rating. The virtual absence of low voltage or CAT 5 cable with 600V insulation rating is why most people simply state that NEC does not allow low voltage cable in the same conduit as 110V wiring.

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I need to get 12V DC/3A to the PTZ camera. If I add another camera for fun (like a bird house camera), it would need either, 12VDC/1A or run 48V POE.

Now that I’m thinking it through, it sounds like I should consider just running DC to the camera…will DC travel 70’?

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Yes, but plan to use use heavier gauge wire. Let’s say you use 12 ga wire.

According to this table, Electrical Wire Gauges

That is 1.6 ohms per 1000 feet. You said 70 feet. That can be either 70 feet from the house to the camera or 35 feet to account for both a power and a ground wire.

Let’s presume 140 feet of wire for both. 140 is about 1/7 of 1000, so the resistance of 140 feet of 12 ga wire is about a quarter ohm. At 3 amps, you will lose about .75 V from the resistance of the wire, leaving 11.25 V for the camera. Is that enough? If not, you need even heavier wire.

The advantage of a higher voltage is lower current for the same amount of power and the resistance loss goes down.

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You will get D.C. through the 70 feet, but voltage drop may be a problem, especially at 3A. Considering the possible cost of running a second conduit for AC power, I would suggest the following. Feed the line with a 24VDC power supply, and use a 24->12 VDC converter rated for at least your 3A requirement. Then you will only have half as much current and voltage drop in your long run. And any good D.C.->DC converter will tolerate considerable fluctuation in input voltage while providing stable output.

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Yep. Run > 12 volts over the line and use a buck converter to drop it down to where you need it. 24VDC at 2 amps should allow you to get 12VDC at 3 amps even with voltage loss from the line and conversion inefficiencies from the buck converter.

A converter like this one would probably work for you:

https://smile.amazon.com/RioRand-3-01-0076-Converter-Module-1-23V-30V/dp/B008BHAOQO

If the camera can use POE and you’re already running Ethernet then why wouldn’t you use POE? Maybe I’m missing something here. This sounds like exactly what POE is for.

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Get a passive power over ethernet adapter set like this:
https://www.amazon.com/dp/B01HMNJHII

and test to see if the voltage is in the range you need at the distance you need. For instance, you may need to put a 15v power supply on for 12v at the far end.

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@lukeiamyourfather The initial camera is not POE. It is a larger PTZ that uses a separate 12VDC/3A powerbrick. Currently I run it from the garage, clamped to the fence by the garage door using passive PoE injectors to carry the power (about a 15ft cable). I initially used a 50ft Ethernet cable, and it did not carry enough power through. I had to run a electric extension cord and run the brick outside until I swapped out to the shorter cable.

This looks like something you might be interested in

https://www.raspberrypi.org/blog/naturebytes-weatherproof-pi-and-camera-case/

That seems like a nice box…still need to get the power to it…