V3 cams connection with long cables

So I ran a 40’ flat cable from inside and connected 2 V3 cams using OTG splitter at the end. This setup works fine when I test with a small cable, but if the same setup is connected at the end of 40’ cable, it does not work. The distances causes impact? I tried to feed power with 2A adapter as well, it does not work.

I searched for answers here but I could not find.

The cable may be the problem. Does it work for one camera?

Yes works for 1, cable looks good… Also both cams power on, but fails to open.

The wire size in most USB cables is pretty small. That results in two major issues. First is that the current carrying capability is rather small, and second, the voltage drop gets pretty large with any significant cable length. That latter part is made worse by the fact that USB in most cases is using a low voltage (5 volts) with a small acceptable voltage range. Put all that together and long cables don’t generally work well - and as the current goes up (two cameras for example vs just one), the voltage drop gets worse so the cable length that will work gets shorter and shorter.
Assuming no possibility of getting 120VAC out to where you need to power the two cameras, your best solution would be to run a higher voltage (12 or 24 V DC comes to mind) over larger wire (16 or 18 AWG comes to mind), and regulate that down to 5 volts needed by the cameras at or near the cameras. I am doing that at my front porch where I have three V3 cameras, and no practical way to get either 5 volts or 120V AC to them. But I do have plenty of 12V DC power available nearby. I have a small box with 4 separate 5V 1A regulators in it. Each outputs to a USB A Female jack and each camera plugs into one of those jacks.


Here is some good info on this thread.


40 feet is a long way. You likely are dropping too far in voltage thru the lossy cable.

Here is some reading on the subject, with several other solutions that people have added to the thread:

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I run three cameras of a 40 feet cable but one cable per camera. The voltage drops from 5V to 4.85V barely scratching the v3 requirements. On those cameras I have hard time keeping the siren consistently going. I get choppy sound. Your single cable feeding two cameras probably drops the voltage below 4V. I would run two separate 40ft cables, one for each camera. It should work as long as you are using 2.1Amp power supply. On a 40ft cable the 1Amp power supply that comes with v3 will not work satisfactory. That 1Amp will probably drop to half Amp.

Thanks, it works perfectly fine for 1 cable - 1 cam, just wanted to avoid 2 cables, but looks like it is going to be 2 cables.

You can do that with a dual USB plug like this one.

I have considered these myself, but note that it has a grounding prong, that means you can only use one of these in a duplex plug, in the bottom plug (assuming your duplex plugs have the ground prong at the bottom), because the grounding prong forces it to be mounted in one direction only.

However, the specs (and reviews) indicate that the grounding prong is not actually electrically part of the circuit (“3-prong (NOT Grounded) design”), so someone in the reviews has suggested that you can tear out the grounding prong with pliers without affecting its functionality, and then you might be able to use two in a duplex plug - one pointed up and the other pointed down.

The dimensions make it appear that the prongs are located close enough to the top end to allow a second one to be plugged in upside down above it (if the grounding prong is removed), but the “pictures” are not real photos (they are digital renderings), and it is difficult to determine from these fake photos, and from the dimensions and the location of the prongs, if it might block the ability to place a second one upside down in the other duplex plug.

On power output, notice that they say it is a 12W max output. At 5 volts, that is 2.4A max. It is unclear whether that 12W is per USB port, or overall. But the specs also indicate "3.1A max, up to 2.4A per port", which essentially means that you will have roughly 1.5A per port with 2 (identical) devices plugged in.

From other discussions in the forums about the V3, it seems that we need to supply each V3 with 1A, and maybe a little more if running longer than normal cords. So it seems if this will provide 1.5A per USB port, that seems like it would be enough to use a longer than normal cable.

I’ve been trying to find something equivalent, that only has 2 prongs in the first place, with dimensions that will allow 2 to be plugged into a duplex plug, and that will provide a bit over 1A per USB port (at 5V). There are several other dual power adapters available on Amazon with 2 prongs, some with foldable prongs, some with fixed prongs, and they all look like they do not have “polarized” prongs, so they could be used in either direction (up or down). But I have not gotten around to trying any to see if they will provide enough amps and voltage for longer cables, and to see if their dimensions and prong positions will allow two to be used in the same duplex plug.

I would cut it off instead prying.

That’s correct. One of my plugs is feeding two cameras. One with 6 ft cord the other with 42 ft cord. Everything works fine except the one on 42 ft cord struggles with siren and two way radio.