RJ45 Camera Cable: What the Pigtail Wires Are For

The short bundle of wires hanging out of an RJ45 camera is called the pigtail, and on most models it carries an RJ45 network socket (which can also deliver power if the camera supports PoE), a round DC power jack, a reset button, and sometimes audio or alarm leads. You only need one power source and one network connection (a PoE cable can be both), so it is normal for several plugs to stay unused. What matters is that the connectors you use are sealed against water, the ones you do not use are capped, and the tail itself is never cut, pinched or left hanging in the rain.

Below: what each lead does, which ones your setup needs, and how a damaged tail shows up as camera faults.

Why IP cameras have a pigtail at all

An outdoor camera body has to be sealed, so the manufacturer brings every connection out through a single sealed cable instead of putting sockets on the housing. The result is a short tail with several plugs on the end. It looks intimidating the first time you unbox it, but each connector has a single job.

Indoor and Wi-Fi models often have a much simpler tail, sometimes just a power jack and a network socket, or no tail at all. Outdoor bullet and dome cameras tend to have the fullest bundle. Exactly which leads you get varies by model, so keep the manual or the small diagram that usually comes in the box, or check the label on the cable itself.

What each wire on the pigtail does

Lay the tail out on a table and identify each connector before you mount anything. Here is what you will usually find.

The RJ45 network socket

This is the female socket that looks like a wider phone plug, usually with a rubber or plastic cap. A standard network cable from your router, switch or recorder plugs in here.

• On a wired network camera, this is how the camera reaches your network and the internet.
• On a camera rj45 poe model, the same cable can also carry power from a PoE switch or a PoE recorder, so you do not need a separate power supply.
• On a Wi-Fi camera, the socket is optional: you can leave it capped and run on Wi-Fi, or plug in a cable for a steadier connection. Our guide on how to connect a Wi-Fi camera with an Ethernet cable covers that setup step by step.

Not every camera with an RJ45 socket supports PoE. If the label, the box or the manual does not mention PoE, assume it does not, and power it through the DC jack instead. A full walkthrough of switches, recorders and cable runs is in the PoE camera setup guide.

The DC power jack

The round barrel socket, often marked DC or with a voltage printed next to it, is for a plug-in power adapter. Check the label on the camera or in the manual for the correct voltage and polarity, and use the adapter supplied with the camera or one the seller confirms matches it.

If you are powering the camera through PoE, leave this jack empty and capped. You do not need both. Plugging in an adapter as well as PoE gives you no benefit, and the safest approach is to use one power source only unless your manual says otherwise.

The reset button

Many tails have a small button, sometimes under a rubber cover, sometimes a short lead with a button at the end. On most models, holding it returns the camera to factory settings, which clears the saved Wi-Fi details and device password. Do not press it to "see what happens". If you do need it, read how to reset a Yoosee camera first so you know what will be erased and how to add the camera back to the app afterwards.

On some models the reset button sits on the camera body or inside a cover instead of on the tail. Check the manual for your model.

Audio in and audio out

Some cameras have two extra leads, often with small round connectors or bare ends, labelled for audio input and audio output. Audio in is for an external microphone; audio out is for an external speaker. Many cameras already have a built-in microphone or speaker, in which case these leads are only for upgrades. If you are not adding external audio equipment, leave them alone and seal or cap the ends.

Alarm in and alarm out

On some models you will find thin wires labelled alarm in, alarm out, or with a ground wire alongside. These connect to external sensors (such as a door contact) or to a device the camera can trigger (such as a siren or a light relay). The colours and wiring differ between models, so follow your manual exactly. If you are not using them, keep the bare ends separated, insulated and dry so they cannot touch each other.

The waterproof kit

Many outdoor cameras come with a small bag of parts: a threaded sleeve, a rubber seal and a cap that screw over the RJ45 socket. This kit lets you pass a network cable through the sleeve, crimp or plug it in, and tighten everything into a sealed joint. It is easy to lose this bag with the packaging, so set it aside before you start.

Which connectors you actually need

Most setups use only one or two connectors on the pigtail. Pick your setup and leave the rest capped:

1. PoE camera with a PoE switch or recorder: use the RJ45 socket only. One cable does power and network.
2. Wired camera without PoE: use the RJ45 socket for the network and the DC jack for power.
3. Wi-Fi camera on Wi-Fi: use the DC jack only. Leave the RJ45 socket capped.
4. Wi-Fi camera on a cable: use the DC jack for power and the RJ45 socket for the network.

Audio, alarm and reset leads are extras. You can install and run a camera perfectly well without ever touching them.

How to protect the pigtail outdoors

Water getting into the pigtail joints is a frequent cause of an outdoor camera dropping offline months after installation. Follow these steps in order:

1. Switch off power before you work. Unplug the adapter or disconnect the PoE cable at the switch before handling connectors. If you are working near mains wiring, on a ladder or on a roof, use a qualified electrician and follow safe ladder practice.
2. Bench test first. Connect the camera on the floor, add it to the app, and confirm live video before any cable goes through a wall.
3. Fit the waterproof kit on the RJ45 joint. Pass the cable through the sleeve and rubber seal before you plug it in (with a ready-made cable, check whether the seal is split to fit around it, or thread the parts on before crimping the plug), then screw everything together firmly by hand.
4. Cap every unused connector. Use the caps supplied. If a cap is missing, wrap the connector with self-amalgamating tape rather than leaving it open.
5. Put the joints somewhere dry. The best place for the tail is inside a junction box, inside the wall or under an eave. If you are also fitting a hood or housing, our article on outdoor camera housing for rain and glare explains how cable entry and drip loops fit together.
6. Leave a drip loop. Let the cable dip below the entry point before rising into the wall, so water drips off the bottom of the loop instead of running into the hole.
7. Seal the wall hole. Use an outdoor sealant around the cable where it enters the building.
8. Do not let the tail carry weight. Clip the main cable to the wall so the pigtail is not hanging or being pulled by the cable run.

What a damaged pigtail looks like

A damaged or wet tail often causes faults that look like Wi-Fi or app problems. Match the symptom to the likely cause before you replace anything:

• Camera goes offline after rain, then comes back when dry: water in the RJ45 joint or the DC jack. Dry it, reseal it, and move the joints somewhere sheltered.
• Camera keeps rebooting: unstable power. On PoE, check the cable and the switch port; on an adapter, check the plug is fully seated and the adapter matches the label. A corroded DC jack can cause this too.
• The link light on the switch port goes out, or the camera drops at random: a loose or corroded RJ45 joint, or a poorly crimped plug on the cable. Re-terminate the plug and test the cable with a cable tester.
• Green or white crust on the pins: corrosion from moisture. Light corrosion can sometimes be cleaned when the power is off, but heavy corrosion usually means the tail needs repair or replacement.
• Camera works on the bench but not on the wall: often the long cable run or a bad connection at the far end, not the camera. Swap in a short known-good cable to compare.
• Night vision flickers or the picture freezes when the infrared turns on: power is marginal. The infrared lights usually make the camera draw more power at night, so a weak adapter or an overloaded PoE switch shows up first after dark.
• Visible cuts, kinks or crushed sections in the tail: physical damage. Do not tape over a split jacket and hope; water will travel along the inside of the cable.

Can a cut or damaged pigtail be repaired?

Sometimes, but it is a job to approach carefully. The tail contains several small wires, and a joint made outdoors without proper seals is likely to fail again. Before you cut anything:

• Check whether the camera is still under the seller's warranty, because cutting the tail may affect that. Ask the seller first.
• Ask the seller whether a replacement tail or replacement camera is available for your model.
• If you do repair a network lead, use proper connectors and test with a cable tester, then put the joint inside a sealed junction box.

Never splice the power leads while the camera is connected, and if the repair involves mains wiring, leave it to a qualified electrician.

When to get help

Contact the seller or a qualified installer if:

• There is fog or water inside the camera housing, not just on the connectors.
• The tail is cut, crushed or melted near the camera body.
• The camera will not power on with a known-good adapter or PoE port.
• You are unsure whether your model supports PoE and do not want to risk it.
• The job needs work at height, on a roof or near mains power.

Have the model name from the label, a photo of the pigtail and a short description of the symptom ready. It makes the conversation much shorter.

Install or resell cameras?

If you fit cameras for customers, the pigtail is a common source of callbacks. Bench test and pair every camera before it leaves the counter, fit the waterproof kit on every RJ45 joint you make, cap every unused lead, and put the tail inside a junction box rather than leaving it exposed under the camera. Label each cable at the switch end, keep a few spare caps and seal kits in the van, and show the customer which single power source the camera uses so nobody plugs in a second adapter later. If you install or sell security cameras and want to discuss supply and dealer terms, see the Yoosee partner information.

Frequently asked questions

Can I cut off the plugs I am not using?

It is better not to. Cutting the tail opens a path for water into the cable and may affect your warranty. Leave unused plugs in place, cap them, and tuck them inside a junction box or behind the camera mount.

Do I need both the DC jack and the RJ45 cable plugged in?

Only if your camera is wired but not PoE, in which case the RJ45 cable carries the network and the DC jack carries power. On a PoE camera connected to a PoE switch or recorder, the network cable alone does both. On a Wi-Fi camera running on Wi-Fi, you only need the DC jack.

Is an RJ45 CCTV camera the same as an analogue camera with a BNC plug?

No. An RJ45 CCTV camera is a network camera that sends its video as data over a network cable. A camera with a round BNC plug is usually an analogue type that needs a compatible recorder, and its wiring is different. Check the connector on your tail before buying switches or recorders.

Why is there a button on the cable with no label?

On many models that is the reset button. Pressing and holding it returns the camera to factory settings, so you will need to pair it with the app again. Check your manual to confirm, because a few models use that lead for something else.

Can I extend the pigtail with a longer cable?

You do not extend the pigtail itself; you plug a longer cable into its connectors. A standard network cable plugs into the RJ45 socket, and a matching extension lead can be used for the DC jack. Keep the joints sealed and dry, and remember that long low-voltage power runs can lose voltage, so test the camera at night before you finish.