A security camera drops offline and the first instinct is to blame the camera. Before you order a replacement, look at the switch it plugs into: the two little LEDs above that port will usually tell you whether you have a cable problem or a power problem. It is a ten-second check, and it happens at ground level.
The two LEDs on every PoE switch port
A commercial Power over Ethernet switch gives each port two separate indicators, and they report on two completely different things. The link LED is about the network: whether the switch can see a physical Ethernet connection on that port, and whether data is moving across it. The PoE LED is about electricity: whether the switch is actually pushing 48 volts down the cable to power the device on the other end.
Because the two are independent, it is the combination that narrows the fault down. One light on its own tells you very little.
Reading the combinations
Link LED completely off. The switch sees nothing connected electrically, even if a cable is physically seated in the port. That means a damaged cable, a bad RJ45 crimp where one of the eight wires never reached the gold pins, a loose plug, or a camera that is not connected at the far end. Nothing here points at the camera yet.
Link LED blinking. Video data is moving across that port right now. This is what a working camera looks like.
PoE LED solid. The switch is delivering power on that port.
Link on, PoE off. This is the useful one. The network side is fine but the switch is not powering the device. Three common causes: a damaged pin or a crimp that caught the data pairs but not the power pairs; a camera that was never designed to take PoE and needs its own supply; or — most often on a system that has grown over time — a switch that has run out of total power to give.
Green versus amber. On many gigabit switches, green means a full 1,000 Mbps link and amber means it has fallen back to 100 Mbps. A camera will often still work at 100 Mbps, but it signals a marginal cable run worth re-terminating before it fails completely. Colour conventions are not standardised, though — some brands invert them, some use a single bi-colour LED — so check the manual for your exact model before acting on a colour. The logic above holds on all of them.
Why the power budget catches people out
Every PoE switch has a total power budget — 120 W, 150 W, 250 W depending on the model — shared across all its ports. Eight standard bullet cameras at 8 to 10 W each sit comfortably inside 150 W. Swap two of them for PTZ domes at 30 W or more and you are suddenly at the ceiling.
When a switch exceeds its budget it does not warn you. It simply stops powering ports. Cameras disappear, recording stops, and it looks exactly like a hardware failure. The lights are what give it away: link on, PoE off, on the ports that dropped.
What we recommend for Kitchener-Waterloo homes and businesses
Local conditions make some of these faults far more common than they should be. Outdoor crimps take a beating over a Waterloo Region winter — freeze-thaw cycles pull moisture into any connector that was not sealed properly, and a damp plug will short the PoE pins and take the camera port with it. If a camera on an exterior wall or soffit goes dark in February, read the lights before assuming the camera is dead.
Long runs are the other one. Farm properties around Cambridge and the townships, and warehouse units with cameras at the far end of a yard, routinely push past the 100 metre copper limit. That shows up as an amber link or a port that drops under load, not as a dead camera.
On new installs our advice is simple: size the switch for the cameras you might add in two years, not just today’s, and leave at least 30 percent of the power budget spare. A larger switch costs less than one callout. And label the ports at the rack — reading the lights only helps if you know which camera each port feeds.
FAQ
My camera is offline but both lights look normal. What now?
If the port has link and PoE, the cable and the power are doing their jobs, so the problem is further up: the camera’s IP settings, a recorder channel that lost its configuration, or outdated firmware on the camera or NVR. Reboot the camera and check whether the recorder still sees it on the network.
Can I use a non-PoE switch for IP cameras?
You can, but every camera then needs its own power adapter and a socket near it, which usually costs more in labour and looks worse than running a single cable. PoE exists so one CAT6 run carries both power and video.
How do I find my switch’s power budget?
It is printed on the label on the underside or rear of the unit as a total wattage figure, and it is in the spec sheet. Add up the rated draw of every camera on that switch and compare. If you are within 20 percent of the budget, treat the switch as full.
If you are looking at a switch and the lights are not telling you a clear story, we will come and look. SpyonSecurity offers a free site survey across Kitchener, Waterloo, Cambridge and Guelph — we check the power budget, test the cable runs, and tell you whether you need a new camera or just a new connector. Call 226-227-7966 or get in touch here.