By the SightShield team · · 3 min read
The switch powers and connects every camera
In an IP CCTV system, a PoE switch carries both data and power to each camera over a single Cat6 cable. If the switch is underpowered, cameras reboot at night when their infrared lights switch on. If its uplink is too slow, video stutters. If it has no surge protection, a lightning strike near an outdoor camera can take out every port. Choosing the switch carefully avoids all three.
PoE standards
Check each camera’s maximum power draw on its data sheet, especially with IR or white lights on, and match the port standard.
| Standard | Name | Power at the switch port | Typical devices |
|---|---|---|---|
| IEEE 802.3af | PoE | Up to 15.4 W | Most fixed dome and bullet cameras |
| IEEE 802.3at | PoE+ | Up to 30 W | Cameras with heaters, strong IR, deterrence lights, small PTZs |
| IEEE 802.3bt | PoE++ | Up to 60 W or 90 W | Large PTZ cameras, multi-sensor cameras |
Total power budget
A switch has a total PoE budget shared across all ports, which is often less than the per-port maximum times the number of ports. An 8-port switch with a 65 W budget can power eight cameras drawing 7 W each, but not eight drawing 12 W at night. Add up the maximum draw of all cameras and choose a switch with at least 20 to 30 percent spare budget.
Other features to check
- Uplink ports: gigabit at minimum to the NVR, or SFP fibre ports for long runs between buildings.
- Port speed: 100 Mbps ports are enough for a single camera; gigabit ports suit uplinks and future devices.
- Extended range mode: some switches support up to 250 metres at reduced speed for distant cameras.
- Surge protection: 6 kV rated ports help on outdoor runs.
- Managed features: VLANs, port monitoring and remote PoE reboot of a hung camera.
- Rack-mountable or wall-mount, and fan noise if it sits in an office.
Managed or unmanaged?
Unmanaged PoE switches are plug-and-play and fine for homes and small shops on a separate CCTV network. Managed or smart switches let you separate cameras into their own VLAN on a shared office network, see which camera is drawing how much power, and power-cycle a frozen camera remotely — valuable for offices, apartments and factories.
Separate network for CCTV (VLAN) →Brands used in India
CCTV brands such as Hikvision, CP Plus, PRAMA and Honeywell sell PoE switches matched to their cameras. Networking brands such as TP-Link, D-Link, Cisco, Netgear, Ruijie and Ubiquiti offer PoE switches with stronger management features. Choose on power budget, port standard, management and local warranty support rather than brand alone.
Placement and power backup
- Put the switch in a ventilated rack or cabinet, not a sealed box in the sun.
- Keep cable runs under 100 metres from switch to camera, or use extended mode or fibre.
- Connect the switch to the same UPS as the NVR and router — if the switch loses power, every camera goes dark.
- Label every port with the camera it feeds.
Example: 12 cameras in a villa
A villa has ten 4MP cameras drawing up to 6 W each with IR on, and two deterrence cameras drawing up to 12 W. Total maximum draw is about 84 W. A 16-port switch with PoE+ on all ports and a 150 W budget gives comfortable headroom, four spare ports for future cameras, and a gigabit uplink to the NVR. It sits in the network cabinet on a UPS sized for the switch, NVR and router.
Right-sized every time
We calculate the power budget for every installation and leave spare capacity, so cameras do not drop out when the lights come on at night.
IT networking services →Quick answers
How many watts does a PoE switch need for CCTV?+
Add the maximum draw of all cameras with IR on and add 20 to 30 percent spare.
Why do my cameras reboot at night?+
Often the PoE budget is exceeded when IR lights switch on. Use a switch with a larger budget.
Do I need a managed PoE switch?+
For homes and small shops, unmanaged is fine. Offices and larger sites benefit from managed features like VLANs and remote PoE reboot.
How far can a PoE camera be from the switch?+
100 metres normally; some switches offer an extended mode up to 250 metres at lower speed.
Can I use the NVR’s PoE ports instead?+
Yes for small systems near the NVR; larger or spread-out sites need separate switches.