How PoE video intercom works
Power over Ethernet (PoE) delivers both electrical power and network data over a single standard Cat5e or Cat6 cable. The entrance panel draws power from a PoE switch port (IEEE 802.3af for up to 15.4 W, or 802.3at for up to 30 W) without a separate power cable or local power supply. The same cable carries the video intercom data — call setup, video stream, door-release signal and management traffic — to the building network.
The advantages for B2B video intercom are: predictable power delivery with switch-level monitoring; no local power supply at the entrance to fail or require maintenance; centralised control through the network switch (power cycling by port, VLAN isolation, QoS); and a clean installation with one cable to the entrance panel. The requirement is a suitable Ethernet cable path from the entrance panel location back to a PoE-capable switch.
How Wi-Fi video intercom works
Wi-Fi video intercom entrance panels connect to the building network over the 2.4 GHz or 5 GHz wireless band. They require a separate power source at the device (typically 12 V DC from a power adapter or a local mains outlet). The entrance panel associates with a wireless access point (AP) and uses the building's Wi-Fi network for call data, video and management.
Wi-Fi entrance panels are most useful in retrofit situations where running a new Ethernet cable to the entrance is not feasible or cost-effective. They trade the cable run for a dependence on wireless coverage quality at the entrance location, AP uptime, and the stability of the network credentials (SSID and password). If the building Wi-Fi network is reconfigured, all Wi-Fi intercom devices on that network must be updated.
Technical comparison: PoE vs Wi-Fi
| Project condition | PoE route | Wi-Fi route |
|---|---|---|
| Power at device | Delivered over Ethernet cable from switch | Local power supply required (12 V DC adapter or mains) |
| Endpoint cabling | Single Cat5e/Cat6 cable to the entrance panel | Local power cable only; no Ethernet to entrance |
| Network ownership | Switch, VLAN, PoE budget, security and maintenance owner | AP placement, coverage, SSID credentials and maintenance owner |
| Retrofit effort | Requires new Ethernet cable if none exists at entrance | Reduces cable work but needs power and coverage verification |
| Reliability | Wired path is predictable; switch port monitoring available | Coverage gaps, interference and AP downtime affect reliability |
| Remote management | Port power-cycle, VLAN, QoS at switch level | Dependent on AP connectivity; no direct hardware reboot path |
| Acceptance | Test power, link state, calls, release and recovery | Test coverage RSSI, roaming or reconnect, calls, release and recovery |
When to choose PoE
PoE is the appropriate choice for the majority of new B2B video intercom installations, and for retrofits where a cable path is available or can be run:
- New construction with structured Ethernet cabling planned for the entrance and riser positions
- Commercial buildings where a managed PoE switch is already part of the building network infrastructure
- Projects where the entrance panel will be integrated with access control, NVR recording or a property management platform — these integrations benefit from the stable, low-latency wired path
- Any project where the property or facilities team needs to remotely power-cycle or diagnose the entrance panel from a switch management interface
- Outdoor entrance panels in environments with significant RF interference from other equipment (e.g., carparks, plant rooms, industrial areas)
When to consider Wi-Fi
Wi-Fi entrance panels are a viable option in specific retrofit scenarios where the wired path is not available and the conditions can be met:
- Retrofit in an existing building where there is no Ethernet path to the entrance and running new cable is not within the project scope or budget
- Low-rise residential projects (villas, small buildings) where the Wi-Fi coverage at the entrance can be reliably provided by the building's existing AP
- Projects where a 12 V DC power supply is already available at the entrance panel location (for example, from an existing access-control reader)
Before selecting a Wi-Fi route, measure the Wi-Fi signal strength (RSSI) at the entrance panel location with the actual AP the device will use. A signal weaker than −65 dBm at the entrance is likely to produce intermittent connectivity issues that are difficult to diagnose and reproduce after the installation is complete. Place a dedicated AP if the existing AP does not provide sufficient coverage at the entrance.
PoE standard and switch compatibility
Most video intercom entrance panels require IEEE 802.3af (15.4 W) or 802.3at (30 W). High-specification entrance panels with heaters, high-resolution cameras or IR illumination may require 802.3at. Verify the specific power requirement for each device type in the bill of materials and compare it against the switch port budget. A switch that is fully loaded across all ports may not have budget for additional PoE devices even if it nominally supports the standard.
Not all PoE-labelled switches are compliant with the IEEE standard; some use a proprietary or passive PoE implementation that is not compatible with standard PoE devices. Verify the switch against the device specification before purchase.
Choose the route from site conditions
- Map the entrance, indoor unit, door release, power source and network owner.
- Survey the cable route for PoE or measure Wi-Fi signal strength at the entrance for Wi-Fi.
- List required functions: call, video, mobile app, access-control integration, NVR recording, simultaneous calls, emergency override.
- Confirm the PoE switch budget (if PoE) or AP placement and signal strength (if Wi-Fi).
- Name who can change the network configuration, replace power supplies and support the device after handover.
- Write and execute the acceptance plan on the constrained endpoint before a full rollout.
PoE vs Wi-Fi video intercom FAQ
Is Wi-Fi always easier for a retrofit?
No. Wi-Fi reduces the Ethernet cable run but requires a local power source at the entrance, sufficient Wi-Fi signal strength (measure it — do not assume), AP stability, and management of network credentials. In a managed building where the IT network is reconfigured periodically, Wi-Fi intercom devices need to be updated after every SSID or password change.
Does PoE remove network risk?
No. PoE delivers power reliably over the cable, but the switch still needs correct VLAN configuration, adequate PoE budget, security policy alignment, and a defined maintenance owner. A switch port with a failed VLAN assignment or an overloaded PoE budget will cause the same intercom outage as a Wi-Fi signal gap. Define the network owner and the troubleshooting process before handover.
Which endpoint should be tested first?
Test the furthest, most constrained or most representative endpoint, and include the door-release response, simultaneous call handling, and power or connectivity failure recovery. For Wi-Fi, test during periods of highest network congestion. An entrance that passes during a low-load test may fail under normal building occupancy.
Can a PoE entrance panel and a Wi-Fi indoor monitor share the same system?
Yes. Many IP video intercom systems support a mix of wired and wireless endpoints on the same platform. The entrance panel typically uses PoE (for reliability), while indoor monitors may use Wi-Fi if Ethernet is not available inside each apartment. Verify the specific model combination is supported by the system controller.
What happens if the PoE switch loses power?
If the PoE switch is on an uninterruptible power supply (UPS), the entrance panel remains operational during a mains power failure. If the switch is not on UPS, the entrance panel loses power when the switch loses power. For buildings with access-control integration, define the power-failure fallback behaviour (fail-safe vs fail-secure) for each door before installation.
Share the building type, entrance panel location, existing cabling and network owner for a PoE or Wi-Fi route review.
Discuss the connection route