How many cameras on which PoE switch?

Q: Does an 8-port PoE switch power 8 cameras?

Not necessarily. What decides is the total PoE budget in watts, not the number of ports. An 8-port switch with a 60 W budget will power four infrared cameras, not eight. Once the budget is reached, the switch cuts ports in priority order — with nothing obvious to warn you, which makes the fault hard to diagnose.

Q: What is the maximum distance over PoE?

100 metres of copper cable between the switch and the device, power included. Beyond that you need fibre with an SFP port and local power, or a repeater. Use category 5e cable as a minimum, and category 6 if you are installing for ten years. See our switch guide.

Count your equipment: we work out the power to reserve, the switch's PoE budget and the minimum standard. An “8-port PoE” switch does not necessarily power 8 cameras — its reserve in watts is what decides, and it is the most common mistake on an installation.

Fixed camera
7 W to reserve · PoE (802.3af)
0
Fixed camera with infrared
13 W to reserve · PoE (802.3af) · the LEDs draw at night
0
Motorised camera (PTZ)
25 W to reserve · PoE+ (802.3at)
0
Heated or extreme-cold outdoor camera
50 W to reserve · PoE++ (802.3bt)
0
Wi-Fi access point
20 W to reserve · PoE+ (802.3at)
0
IP phone
7 W to reserve · PoE (802.3af)
0
IP speaker or siren
13 W to reserve · PoE (802.3af)
0

The PoE standards and what they power

Each standard defines two figures: what the switch supplies at the port, and what is guaranteed to the device after 100 m of cable. The gap is the line loss.

Standard	Supplied at the port	Guaranteed to the device	What it powers
PoE — 802.3af	15.4 W	12.95 W	Fixed camera, IP phone, small access point
PoE+ — 802.3at	30 W	25.5 W	Motorised camera, recent Wi-Fi access point, camera with powerful infrared
PoE++ type 3 — 802.3bt	60 W	51 W	Heated camera, multi-radio access point, signage display
PoE++ type 4 — 802.3bt	90 W	71 W	High-consumption equipment, light workstation

Common installations, already worked out

Installation	To reserve	PoE budget	Min. standard
4 fixed cameras (shop, practice)	28 W	35 W	PoE (802.3af)
8 fixed infrared cameras (villa)	104 W	130 W	PoE (802.3af)
8 cameras, 2 of them motorised	128 W	160 W	PoE+ (802.3at)
16 infrared cameras (warehouse)	208 W	260 W	PoE (802.3af)
CCTV + Wi-Fi (6 cameras, 3 access points)	138 W	175 W	PoE+ (802.3at)

For the same budget, prefer a switch that keeps some reserve: a camera added two years later should not force you to replace the network gear. See PoE switches.

Frequently asked questions

Does an 8-port PoE switch power 8 cameras?

Not necessarily. What decides is the total PoE budget in watts, not the number of ports. An 8-port switch with a 60 W budget will power four infrared cameras, not eight. Once the budget is reached, the switch cuts ports in priority order — with nothing obvious to warn you, which makes the fault hard to diagnose.

Why is the power at the port higher than what the camera receives?

Because copper cable dissipates part of the energy over the distance. The standards therefore define two figures: what the switch supplies at the port and what is guaranteed to the device at the end of 100 m. You always size on the first — that is what is taken out of the budget.

What is the maximum distance over PoE?

100 metres of copper cable between the switch and the device, power included. Beyond that you need fibre with an SFP port and local power, or a repeater. Use category 5e cable as a minimum, and category 6 if you are installing for ten years. See our switch guide.

Do you need a managed switch for cameras?

It becomes useful as soon as you go beyond a few cameras. Management lets you isolate the camera network from the office network with VLANs, prioritise traffic, and above all restart a port remotely to bring a frozen camera back — which saves a site visit. Below four cameras in a single room, an unmanaged model is enough.

Should the installation be protected against power cuts?

Yes, and it is often forgotten: a CCTV installation that stops at every power cut fails to do its job precisely at the most critical moments. The PoE switch and the recorder must be on a UPS. Work out the rating with our UPS sizing tool.