There is a fault that every installer knows: the camera that "disappears" every now and then. The recorder shows it as offline, the customer calls, you go there, unplug the network cable and plug it back in, and the camera is back. No component is broken, no cable is cut: the camera's software has crashed, just like a phone does. The remedy is to cut and restore power, and as long as you do it by hand, it means a site visit, an hour of travel, and a ladder.
The following three functions are found in switches designed for video surveillance and serve exactly this purpose. They don't cost much, few people use them, and they change the life of those who perform maintenance.
The PoE watchdog
The switch sends a periodic ping to the device connected to each port. If the device does not respond after a certain number of attempts, the port is turned off for a few seconds and turned back on: the camera restarts. In the vast majority of cases, it restarts upon reboot and no one notices anything.
Two precautions when configuring it. First: the wait time must be longer than the camera's boot time, otherwise the switch will restart it while it is still starting up, and it will get stuck in a cycle. Sixty to ninety seconds is a reasonable value. Second: put a cap on the attempts. If a camera does not respond after three reboots, the problem is not the software: it's the cable, the power supply, or the camera itself, and continuing to restart it hides the fault instead of signaling it.
The device offline alert
The second function is even simpler: the switch notifies you when a port loses its device. It seems trivial, but try asking yourself how you find out today. In most systems, you notice it when the customer opens the app, and that typically happens when the footage is needed, i.e., the day after a theft.
With a notification from the switch—or from the device's cloud, if it is managed—you know the same day. In a residential complex or a shop, knowing it the same day is the difference between routine maintenance and an argument with the insurance company.
Remote single-port reboot
The third one is the most practical: from the switch interface, even from your phone if the device is cloud-managed, you turn port 7 off and on again. You don't go to the site, you don't restart the whole system, and you don't touch the other eleven cameras that are recording. A customer calls at eight in the evening, you open the app, restart the port, and at eight-oh-one the camera is back.
The rest of the package
The same devices usually come with two other things that come in handy for camera systems. Automatic recognition of video surveillance devices, which shows you on the port map which is a camera and which is a recorder instead of just addresses. And protection against loops: if someone accidentally closes a cable on itself—it happens more often than is admitted, especially in residential electrical cabinets—the switch notices it and blocks the port instead of taking down the whole network.
When it makes sense to spend more
For a four-camera system in a house where you live, an unmanaged switch is perfectly fine: if something crashes, you can unplug and plug it back in yourself in thirty seconds. On a system with twelve or twenty-four shooting points, in a warehouse, in a residential complex, on anything that is far from those who need to fix it, the price difference between managed and unmanaged is recovered on the second saved site visit.
You can find devices with these functions among the managed switches; if you are looking for the essential solution, browse the unmanaged switches and network accessories. To understand which range is best for your system, write to us at info@elettricity.com or call 351 969 5157.