Resourcefulness is paramount when designing IT solutions. In modern networks, Power Over Ethernet (PoE) technology is already proving its ability to extend the life of existing networks. PoE injectors provide a cost-effective way to combine new and legacy devices on the same network.
In the world of modern IT networks, resourcefulness and sustainability are paramount. As technology evolves, it’s important to design solutions that meet contemporary needs while adapting to future demands. One technology that has proven its ability to extend the life of existing networks is Power over Ethernet (PoE). By combining the power of new and legacy devices, PoE enables a cost-effective and efficient approach to network infrastructure.
What is a PoE injector?
PoE injectors, or midspans, turn LAN equipment into PoE systems by connecting PoE-enabled network devices to a non-PoE LAN switch port. They can connect wireless access points, IP phones, network cameras, or any IEEE 802.3af/at-powered device (PD) to a network switch.
Power flows to devices through the PoE injector.
How PoE Injectors Work
Easy to install and use, a PoE injector is a cost-effective way to add PoE functionality to an existing network. An injector has three ports: a power input, a data input, and a power/data output port.
The connection process involves:
- Plugging the PoE injector into a regular power outlet.
- Connecting an Ethernet cable from the injector to a non-PoE switch.
- Connecting another Ethernet cable from the injector to the PoE-enabled device.
The PoE injector detects the PoE-enabled device and supplies it with electrical power via the Ethernet cable.
Types of PoE Injectors
The two main types of PoE injectors are active and passive. They can have either a single port or multiple ports.
Active Injectors
An active PoE injector adheres to standards such as IEEE 802.3af, IEEE 802.3at, or the latest IEEE 802.3bt. Containing a built-in chip for device detection and power negotiation, active injectors regulate voltage and current based on the connected device’s requirements, ensuring safe power delivery.
Active PoE injectors are compatible with a wide range of devices. They are ideal for networks with a mix of PoE devices from different manufacturers and varying power requirements. Injectors offer a future-proof solution that can accommodate potential network upgrades.
Passive Injectors
A passive PoE injector is much simpler than an active injector, though also less nuanced. Passive injectors do not detect the type of PoE device connected and simply inject a fixed voltage of power through the cable. They don’t follow any standards and may not be compatible with all PoE devices. If the voltage provided is too high, it can damage devices on the network.
Passive injectors are less expensive than active injectors and are best used in networks with a few PoE devices requiring the same voltage, such as 24V.
Single-port Injectors
A single-port injector has just one port for injecting power into a single Ethernet cable. These are perfect for situations where only one PoE device needs power, such as a VoIP phone in a separate office.
Multi-port Injectors
Multi-port PoE injectors can deliver power to several devices simultaneously. They are designed to power multiple PoE devices spread across an area, such as security cameras and wireless access points.
When to Use PoE Injectors
A PoE injector offers a flexible and cost-effective way to expand PoE functionality in a network. Situations where a PoE injector might come in handy include:
- A non-PoE switch with PoE devices connected: A PoE injector acts as a bridge, connecting and powering PoE devices such as VoIP phones, IP cameras, and wireless access points. Injecting power into a standard Ethernet cable enables data and power transmission to PoE devices.
- Remote PoE deployment: PoE injectors are perfect for powering PoE devices in remote locations that lack power outlets, such as security cameras on ceilings and outdoor access points. They simplify installation and eliminate the need for separate power cables.
A PoE injector costs less upfront than a PoE switch, especially when using passive PoE injectors for compatible devices.
Advantages of Using PoE Injectors in Hybrid Network Installations
Hybrid network installations combine PoE and non-PoE devices. The key advantages of PoE injectors include:
Scalability
A PoE injector provides a flexible way to gradually introduce PoE devices into a network. It makes it easier to scale up as needs grow, eliminating the hassle of purchasing a new PoE switch when requirements change in the future.
Cost Savings
PoE injectors are a budget-friendly option compared to the cost of purchasing a PoE switch. This is especially true in scenarios where a passive injector will suffice.
Efficient Cable Management
When a PoE injector is used, the need for separate power cables for PoE devices is eliminated. This reduces cable and improves the overall aesthetics of a network installation.
Flexibility in PoE Standard Support
Active PoE injectors can adjust power delivery based on the connected device’s PoE standard (PoE, PoE+, PoE++). This provides more flexibility in mixed PoE environments.
Simplified PoE Deployment
PoE injectors are easier to set up and manage than PoE switches. Requiring minimal configuration, injectors can be quickly deployed to power devices in remote locations where installing power cabling might be challenging.
How PoE Injectors Comply with Power Standards
PoE injectors comply with the IEEE 802.3 power standards for PoE.
Active PoE injectors have a built-in chip that follows the standard’s guidelines to identify the type of PoE device connected (PoE, PoE+, PoE++). Based on the device type and the standard’s power delivery specifications, the injector’s chip negotiates the appropriate voltage and current levels to deliver the right amount of power. Power is supplied by the injector over the Ethernet cable as per the standard’s defined voltage levels. Active injectors offer better safety, compatibility, and overall network performance.
Passive PoE injectors can’t check against PoE standards but rather inject a pre-set voltage over the Ethernet cable regardless of the connected device. While cost-effective, passive injectors can be risky if the voltage doesn’t match the connected devices’ requirements.
Consult the professionals at Planetech USA today to learn more about how to expand your network sustainably with a PoE injector.