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article · CCTV
PoE power budget: choosing the right switch for IP cameras
PoE standards, total switch budget and the 100 m cable limit for stable IP camera installations.
Select Security1 min read
What PoE is
Power over Ethernet (PoE) delivers data and power over a single network cable. The main standards are:
- IEEE 802.3af (PoE): up to 15.4 W per port
- IEEE 802.3at (PoE+): up to 30 W per port
- IEEE 802.3bt (PoE++): up to 60–90 W per port
How to calculate the budget
- Add up the maximum consumption of every camera from the manufacturer datasheet (not the average).
- Compare it with the switch's total PoE budget, not just the port count.
- Keep at least 20–30% headroom for night IR illumination and heaters.
Cabling
The maximum Ethernet segment length is 100 metres. Use solid copper CAT5e/CAT6; CCA (copper-clad aluminium) cable often causes voltage drop and unstable PoE.
Always check a specific model's consumption in its datasheet or ask a Select Security specialist.
#PoE#CCTV#Network
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