IP cameras and PoE power budgets

Skills you'll practise

• Calculate pixel density at a target from a camera's resolution and the scene width, and compare it with the site's requirement
• Identify the IEEE PoE type and class a camera needs and the power available at the switch port and at the camera
• Calculate a switch's PoE allocation for a camera schedule and decide what to change when it is over budget
• Estimate recorder bandwidth and storage from stated bitrates, camera counts and retention
• Apply network separation, credential and privacy basics before handing a camera system over

Course outline

1. 1.IP cameras and PoE power budgetsVideo · 3 min
2. 2.Cameras, mounting and what the camera must seeLesson · 18 min
3. 3.PoE types, classes and switch budgetsLesson · 20 min
4. 4.Recording, networks, passwords and privacyLesson · 18 min
5. 5.IP cameras and PoE power budgets: knowledge checkKnowledge check · 27 questions
6. 6.Cameras go offline every eveningScenario
7. 7.Final exam10 questions · passing it completes the course, so people who already know the material can test out

Sources it draws on

The lessons and questions are written from these references, so learners can go back to the original.

• IEEE 802.3bt-2018: Power over Ethernet over 4 pairs (amendment to IEEE 802.3)
• Cisco Catalyst 9300 configuration guide: Configuring PoE (IEEE classes 0–8 and maximum power per class, power negotiation by CDP/LLDP, first-come allocation)
• Power over Ethernet: summary of IEEE types (Type 1 15.4 W / 12.95 W, Type 2 30 W / 25.5 W, Type 3 60 W / 51 W, Type 4 90 W / 71.3 W at PSE / PD)
• IEC 62676-4: Video surveillance systems for use in security applications, Part 4: Application guidelines
• UK ICO: Guidance on video surveillance (including CCTV): transparency, audio, limiting coverage, DPIAs (UK example; follow the law where you work)