# L7805CV 5V Voltage Regulator to IP camera over POE

I am having a problem with getting my IP cameras to work over my home-made POE cable.

The parts I made in order to have POE are the following:

Now the power supply that comes with it says this:

INPUT: 100-240V- 50/60Hz 0.4A max
OUTPUT: 5V 2A


I noticed when I hook up the original power supply to it-it does not power on. I'm just guessing its because I have the 5V Voltage Regulator in there and its feeding it less than 5V?

But once I connected it up using the POE injectors it works just fine (tested with a ethernet cable about 10ft long or so). Now that I placed them outside I have (again guessing) about ~120ft of ethernet cable from one tree IP Camera to my garage. It's using the direct burial ethernet cable for this (the original test was using a standard ethernet cable).

The power is coming from the 12V 2A DC Power Adapter Supply hooked into the POE injector. From there the POE injector is hooked to the switch and the other end to the direct burial ethernet cable that's going outside to the IP Camera. At night I can see the glow of the red IR LEDs so I know it's getting power. And I also see that its blinking (green led) on the switch so I know it's communicating... But when I try to find its IP on my router it does not show up at all?

And again, I tested this out using the 12V 2A DC Power Adapter Supply/ POE injector and a standard 10ft ethernet cable and it worked just fine.

I tested the voltage with a volt meter to make sure it was getting enough from that long run. I had 12V on one side (the garage) going through the injector/ethernet wire and on the other end (outside at the other injector from the ethernet) I had about 12.4V constant so it really did not drop at all from that 150ft ethernet run.

I also tested to make sure my crimping on the ends of the ethernet were correct (had a gizmo that sent out a signal and showed me what order the wires are in). They all came back the same.

So what all should I try testing out first? Second? Third? I already heat shrink all the connections outside so I hope I don't have to pull those apart to disconnect the POE/splitter!

## 2 Answers

Even thought the pins are connected in the right order between the two RJ45 connectors, they still might be using the wrong wires. It's important that the twisted pairs are matched up correctly. Did you follow T568B?

• I made sure that both ends of the ethernet cable were the same order. I ordered them from pin1-8 [Green|Green white|Orange}Orange white|Blue|Blue White|Brown|Brown White] which would mean that its the same no matter what. I also tested to make sure my crimping on the ends of the ethernet were correct (had a gizmo that sent out a signal and showed me what order the wires are in). They all came back the same Nov 14, 2012 at 16:24
• Your wiring is definitely wrong. Pin 1-8 cannot be connected in that way. That's my point. Certain pairs of wires are twisted together, and those pairs need to be on certain pains. Having them in the same order at both ends is not enough. For example, pin 3 and pin 6 need to be on the same color pair. Nov 14, 2012 at 16:26
• That would not make since since (for example) pin 1 is a Green wire on both ends. I understand there are standards but this is just a home hookup. The Injector takes care of the POE/Data.. not the ethernet pin out itself. Nov 14, 2012 at 18:33
• I will state it again: Your wiring is definitely wrong. It will not work. Ethernet requires that the wire connected to pin 3 is tightly twisted together with the wire connected to pin 6. In your case, one of them is orange, and the other is blue-white. They are not twisted together inside the cable, and that is why it's not working. Nov 14, 2012 at 18:53
• This is an ancient thread so I'm not sure why I'm following up, but I just wanted to mention that it's just a matter of recrimping new terminators on the ends of the cable to fix this. It's not much work if you still have some slack. Yeah... the power will work fine, but the ethernet signaling will not work when the twisted pairs are not properly utilized. May 22 at 23:20

First of all, you should measure your voltage while the load at its peak of power consumptions, which means your IP camera IR is switched on. You should'nt disconnect the load and check the voltage, which aparently there is no current circulation which means no voltage drop. If you measure it while Camera is connected, you most likely having around 5-7 VDC.

Your problem the power supply it doesn't regulate the voltage drop by increasing the voltage input and maintaining a set-point of 12 volts all the time.

In case of having low voltage, you can't predict what type of functionality and behavior your camera will have.