How to Size a PoE Switch

Match device count and PoE budget to real-world CCTV, intercom and AP loads. This guide is written to be practical, clear and useful for Australian readers planning low-voltage, communications and security-related cabling projects.

Detailed guidance

This guide focuses on clear communication, predictable installation work and maintainable systems. A good document should tell the reader what the system is, what cable is used, how the devices connect, where power comes from and how future technicians will identify everything later.

Where possible, make the guide specific rather than generic. Name cable types, explain why they are used, give examples of labels, and show how the diagram relates to the real site. Readers find a guide far more useful when it explains practical trade-offs rather than just listing buzzwords.

Step-by-step checklist

Useful reminders

• Keep device labels consistent between the site plan, cable schedule and the final diagram.
• Note spare ports, spare conductors and cabinet space for future additions.
• Photograph cabinets, terminations and field devices once the job is complete.
• Record deviations from the original design so the as-built drawing stays accurate.
• Where life-safety or egress are involved, always refer back to the relevant manufacturer and compliance requirements.

Related diagrams

Related guides

• How to Plan a School CCTV System
• How to Choose a UPS for Security Equipment
• How to Plan a Small Office Security Fitout
• How to Troubleshoot an Intercom Door Release
• PoE Planning Guide
• When to Use Fibre Instead of Copper