Power over Ethernet (PoE) technology enables a common cable to deliver current to run devices, as well as data packets for connecting these to a network. It can be a powerful tool to ease operations and to maintain essential enterprise appliances, and eventually reduce expenses and downtime.
Where PoE can be applied
Businesses can use PoE to run most of their network-based appliances and data loggers, which require reliable, consistent and uninterrupted power as well as network. Sumit Thukral, CEO, Rational Systems Pvt Ltd, says, “The technology is majorly used with network-based devices like Internet Protocol (IP)-based surveillance cameras, Wi-Fi access points and routers, IP phones and so on, where a dedicated data channel and scalable powering is necessary. It is more profitable in large-scale deployment scenarios like large hotels, hospitals or offices, where powering each individual device with separate current source and Ethernet cable is cumbersome and expensive. PoE can be highly beneficial for low-power wireless devices as well.”
A spokesperson from Infonet Solutions adds, “Power over ethernet can also be used in industries for various data acquisition devices and programmable controllers. Telecom and Internet service providers are big users of the technology. For instance, it can power server units and provide dedicated network connectivity through a single cable.”
Further applications include radio-frequency identification (RFID) and access controls, industrial lighting systems, attendance systems, Voice over IP (VoIP) phones, building automation setups and so on.
A basic PoE connection for surveillance camera using PoE injector (source: http://www.veracityglobal.com/)
A usual setup of a PoE system starts with a PoE network switch that combines power and data input, and channels these through a cable—usually a standard CAT3, CAT5 or CAT6 cable. It then connects to the powered device, that is, the target device or appliance.
Other setups may include devices like PoE injector, which adds power to a data-only source, or PoE splitter that separates power and data channels based on powered device compatibility.
Benefits of PoE
PoE can bring an array of benefits, including expense reduction, ease of maintenance, quicker servicing and reliable connectivity.
Cost optimisation. Thukral mentions, “The major advantage of PoE is that local power is not required for individual devices. Primary cost savings come in the form of reduced excess wiring and cabling. That itself cuts down the installation cost and labour charges significantly.”
PoE setups and components usually have a 10 to 20 per cent higher price tag, compared to traditional hardware. However, installation cost and overall operational efficiency make up for this higher expense.
Thukral continues, “Collaterally, a single power and Ethernet source means easier maintenance. Only one backup unit is sufficient for all services over a PoE cable. There is no need for installing multiple local power outlets either.”
All these lead to an eventual cost optimisation of 30 to 50 per cent in setup, operation and maintenance.
Higher reliability. Normal power cables are prone to wear-and-tear and damage. PoE cables are comparatively resilient. There is a strong safety factor with PoE. A low-voltage test current is initially passed through PoE cables to test resistance and safety standards in place. Full power is channeled only after ensuring this.
On the other hand, wireless communication is prone to signal interference. This can be problematic in case of essential devices such as surveillance cameras, data loggers and routers. PoE cables keep the risk of interference at bay.
There is a certain reduction of downtime as well. Thukral says, “Users get a chance to keep an eye on the operation of all connected devices in real time. It is easier for them to manage the common point in PoE compared to distributed devices, making troubleshooting easier.” PoE systems can usually be invigilated and controlled through graphical user platforms.
Flexibility. Users can retrofit the installation on their existing non-PoE appliances as well. For instance, if they own a general (non-PoE) network switch but have a PoE-enabled powered device, then a PoE injector acts as a bridge between the two, adding the power line along with data stream from the switch (as shown in the figure above).
On the other hand, if a single powered device in the setup is not PoE-compliant, while a source PoE switch is available, a PoE splitter can separate the power line from data coming from the switch and run the powered device as required. Moreover, PoE is a scalable solution and allows powering of appliances across long distances.
Final word
PoE has been picking up popularity for a few years now. While buying the hardware can be comparatively costly initially, application in the right areas of business can derive a quick and assured ROI.
