When setting up or upgrading a network, Power over Ethernet (PoE) is a game-changer. It delivers both power and data over a single Ethernet cable, reducing clutter, simplifying installation, and cutting costs.
However, not all PoE is the same. You’ll often see two terms—Active PoE and Passive PoE —and choosing the wrong one can lead to compatibility issues or even damage your devices. So, what’s the difference, and which one should you choose? Let’s break it down.
What is Active PoE?
Active PoE, also known as standard PoE, follows official IEEE standards (802.3af, 802.3at, and 802.3bt). The key advantage is that Active PoE devices have smart power detection—the ability to identify whether the connected device supports PoE before delivering power.
When you connect to a device — such as a Wi-Fi access point or IP camera — an Active PoE injector like Omada PoE150S, PoE170S, or PoE260S, automatically checks whether the device supports PoE. It delivers power if the device is compatible, ensuring safe, reliable, and energy-efficient operation.
This built-in handshake protects your equipment from over-voltage and mismatched connections, making Active PoE the preferred choice for modern business and enterprise networks.
Imagine deploying an Omada EAP772 Access Point, equipped with a 2.5G Ethernet port, in an area without nearby power outlets. By pairing it with an Omada PoE260S active PoE injector, which complies with the IEEE 802.3af/at standard and delivers up to 30 W of power over the same 2.5G connection, you can supply both power and data seamlessly over a single cable. This setup ensures safe power delivery and reliable data transmission.
What is Passive PoE?
Unlike Active PoE, Passive PoE does not follow IEEE standards. It delivers a fixed voltage —commonly 24 V or 48 V—over Ethernet without automatic detection or negotiation.
This means power flows as soon as the cable is connected, whether or not the device is PoE-compatible. While this approach makes Passive PoE injectors more budget-friendly, it also increases the risk of permanent damage to your device if the voltage doesn’t match your device’s requirements.
Passive PoE is suitable for simple, cost-effective, or legacy network setups, such as certain outdoor access points or radio antennas. It's ideal for small offices, warehouses, or basic surveillance systems that don’t require full IEEE compliance.
For example, if you’re powering an outdoor AP that specifically supports 24 V Passive PoE, a compact adapter like Omada POE2412G can provide steady current. However, using higher-voltage models such as POE4818G or POE4824G on incompatible devices may result in permanent damage.
When use Passive PoE injector, always double-check your device specifications.
Active vs Passive PoE: Quick Comparison
| Feature | Active PoE (Standard) | Passive PoE (Non-Standard) |
| Compliance | IEEE 802.3af/at/bt | No official standard |
| Device Detection | Yes, smart negotiation | No detection |
| Safety | High, prevents device damage | Low, risk of over-voltage |
| Voltage | Auto-adjusts (e.g., 48V) | Fixed 24V/48V |
| Cost | Medium to High | Low |
| Common Use | Enterprise APs, IP phones, cameras | Consumer APs, DIY projects |
Which PoE Option Should You Choose?
Omada offers a full range of PoE solutions tailored for every networking need:
Passive PoE Injectors
For budget or legacy equipment, Omada PoE adapters — including PoE2412G, PoE4818G, and PoE4824G — deliver reliable performance at an affordable price.
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PoE2412G – 24 V / 12 W, ideal for Omada EAP225 V3 and EAP225-Outdoor.
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PoE4818G – 48V / 18W. It's compatible with Omada EAP650-outdoor.
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PoE4824G – 48V / 24W. It provides higher power output for devices, ensuring stable and consistent performance.
Tips: If your device draws less than or equal to 18W (at 48V passive PoE), PoE4818G is a cost-efficient option. For devices that require up to 24 W, choose the PoE4824G to ensure sufficient power delivery and prevent performance instability.
Active (Standard) PoE Injectors
For enterprise-grade networks, choose from Omada POE150S, POE160S, POE170S, or POE260S, POE380S—all engineered for safety, flexibility, and compatibility with the majority of PoE devices on the market.
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POE150S- A Gigabit PoE injector compliant with IEEE 802.3af, delivering up to 15.4 W of power. Ideal for powering low-power devices such as access points, IP cameras, or VoIP phones.
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PoE160S- A PoE+ injector supporting IEEE 802.3af/at with up to 30 W output, providing reliable Gigabit data transmission and easy plug-and-play installation for small business networks.
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PoE170S- A high-power PoE++ injector supporting IEEE 802.3af/at/bt standards with durable metal casing, delivering up to 60 W of power for devices with higher energy needs such as Wi-Fi 6 access points or PTZ cameras.
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PoE260S- A 2.5 Gbps PoE+ injector that provides 30 W of power and faster data speeds for next-generation Omada Wi-Fi 7 Access Points, ideal for high-bandwidth applications.
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PoE380S- A 10 Gbps PoE++ injector supporting up to 90 W output with full IEEE 802.3bt compatibility and durable metal casing, designed for enterprise-grade equipment requiring maximum power and ultra-high data throughput.
Whether you’re powering IP cameras, access points, or VoIP phones, Omada PoE adapters and injectors give you the confidence of secure, scalable, and future-ready networking.
Choosing between Active and Passive PoE depends on your devices and power requirements. With Omada’s full lineup of PoE injectors and adapters, you can build a network that’s efficient, reliable, and built for the future.