A supermarket owner recently called me in panic.
“We connected 8 cameras to an 8-port PoE switch, and now none of them work. Are all your cameras defective?”
When I arrived on-site, the cameras were perfectly fine.
The real problem?
The PoE switch.
This is one of the most common mistakes in CCTV projects.
Many buyers assume:
8 PoE ports = 8 cameras.
Unfortunately, that’s not always true.
The hidden factor is something called the PoE Power Budget.
What Is a PoE Power Budget?
Every PoE switch has two important specifications:
1. Number of Ports
This tells you how many devices can be connected.
2. Total PoE Power Budget
This determines how many devices can actually receive power simultaneously.
Many low-cost 8-port PoE switches provide:
- 60W total power
- 80W total power
- 96W total power
At first glance, this seems sufficient.
But let’s calculate.
The Simple Math Most Buyers Ignore
A typical IP camera consumes:
- Fixed camera: 8W-12W
- AI camera: 10W-15W
- PTZ camera: 20W-30W
- Speed dome: 30W+
Suppose each camera consumes 15W.
8 Cameras × 15W = 120W
If the switch provides only 60W or 96W total output, the switch will become overloaded.
Usually:
- First few cameras power up
- Remaining cameras stay offline
- System becomes unstable
- Random camera disconnections occur
The cameras are not broken.
The switch simply cannot provide enough power.
Why Cheap PoE Switches Create Expensive Problems
Many budget switches advertise:
“8-Port PoE”
But hide the actual power budget in small print.
Some even exaggerate their specifications.
A switch labeled as 120W may deliver only 80W under real-world conditions.
For CCTV projects, this can lead to:
- Camera outages
- Video loss
- NVR recording interruptions
- Costly troubleshooting visits
PoE vs PoE+
Another common mistake is confusing PoE standards.
IEEE 802.3af (PoE)
Maximum power:
15.4W per port
Suitable for:
- Fixed IP cameras
- Basic indoor cameras
IEEE 802.3at (PoE+)
Maximum power:
30W per port
Suitable for:
- PTZ cameras
- AI cameras
- Dual-lens cameras
- High-performance outdoor cameras
If your camera requires 25W and your switch only supports standard PoE, the device may never start properly.
Recommended PoE Power Budget
| Number of Cameras | Recommended Minimum Power |
|---|---|
| 4 Cameras | 60W |
| 8 Cameras | 120W-150W |
| 16 Cameras | 240W-300W |
| 24 Cameras | 370W+ |
| 48 Cameras | 740W+ |
Always leave 20%-30% reserve capacity for future expansion.
Quick Power Calculation Formula
Use this simple rule:
(Number of Cameras × Camera Wattage) × 1.2
Example:
8 Cameras × 15W × 1.2
= 144W
Recommended switch:
150W PoE budget or higher.
Additional Installation Tips
Avoid Mixing Unknown Brands
Some non-standard PoE implementations may create compatibility issues.
Check Future Expansion
If you plan to add cameras later, buy a larger switch today.
Don’t Focus Only on Price
A $30 saving on a switch can result in hundreds of dollars of troubleshooting costs later.
Verify Real Power Budget
Always check:
- Total PoE Budget
- Per-Port Maximum Output
- PoE Standard (802.3af / 802.3at)
Final Thoughts
In CCTV projects, the number of ports is only half the story.
The real question is:
Can your switch provide enough power to every camera simultaneously?
Before buying any PoE switch, calculate the total power requirement first.
A correctly sized PoE switch means:
✓ Stable cameras
✓ Reliable recording
✓ Fewer service calls
✓ Better customer satisfaction
And most importantly…
No more blaming perfectly good cameras for a power problem.
Looking for Reliable PoE Surveillance Solutions?
At SNOSECURE, we help security brands, distributors, system integrators, and project contractors build reliable surveillance systems with:
✔ NVR Kits
✔ Video Doorbells
✔ AI Surveillance Solutions
✔ OEM & ODM Customization
With 20 years of manufacturing experience, 6 production lines, and an 12,000m² factory, we support customers across North America, Europe, the Middle East, Africa, and Asia.
Whether you need a complete surveillance solution or customized products under your own brand, SNOSECURE can help you reduce risk and improve project reliability.
Contact our team today for product recommendations, OEM branding options, and project support.
WhatsApp: +86-185-6568-6066
Website: www.camhiprocam.com
