PoE is not just “Power over Ethernet.” PoE(Power over Ethernet) is usually understood as “Powered via network cable.” This meaning is not wrong, but stop in the surface. The true PoE meaning not only ignored power supply but also happen a fundamental changes in the Power supply method.
In a traditional structure, each device is powered by an independent power supply and disperses the responsibility. And in the PoE system, power is concentrated in a switch or a power device, that mean the stability, continuity, and safety all bear for the whole system. Once the power supply is centralized, any design or selection will be a little different, which will be amplified to the entire network. Therefore, PoE is not only a simple feature choice but is a powered-by solution for the system
A PoE switch is often selected as an ordinary network, bu actual it plays the role of PSE. The PoE switch needs to deal with data transmission, and respond to many terminal equipment for continuous, stable power.
In actual application, the problem does not happen in network performance, but happens in power capacity. The number of ports and nominal power parameters do not all reflect true power performance. When many device opeation, start in a same time or load work for a long time, the switch power allocation strategy and continuous capacity is a true test.
The potential risks of PoE convenience
The importance of PoE is widely use is plug and play. But this convenience lets many potential risks be ignored. Not all network devices support PoE power. Some Non-PoE devices, old devices, or custom devices in a direct access PoE network that will long-term exposure in unnecessary voltage envirment. Even if PoE has a certain automatic identification mechanism, that doesn’t mean it’s safe for application.
As the PoE is used for industry, commerce, or highly reliable systems, each power supply anomaly may bring a risk for the device to break or cause a system shutdown.
When must we use the PoE filter?
The PoE filter effect not only increases performance but also isolates risk. Its core feature is block the power voltage of Ethernet, only keep data transmission, and protect terminal devices that do not support PoE.
In a hybrid deployment environment, a PoE filter is important. If the same network saves a PoE device and a non-PoE device at the same time, the PoE filter provides clear physical isolation that avoids wrong connection or wrong power bring a risk.
A PoE filter is not a necessity for each system. And the cost of errors is high, it is a necessary and reliable design choice.
PoE cameras are a common and ignored load.
PoE cameras are a common type of terminal in PoE applications, but are easy to ignore. Compare the static network device differences, the PoE cameras’ power consumption does not constantly change.
At the start stage, night vision mode changes, or when the infrared fill light is turned on, the cameras will experience power fluctuations in short time. Many cameras operate at the same time, which will increase and create continuous power supply pressure on the PoE switch.
Many PoE systems operate normally in the initial stages, but appear unstable appearance in use for a long time. Its root cause is not in the cameras themselves, but in the system design of insufficient power supply capacity.
A reliable PoE system, not starting design from the network cable or number of ports, but also based on the actual needs of the end devices.
We understand the PoE power property, a reliable choice of PoE switch, and pull in a PoE filter in a necessary application. These are a part of the system design. Under the premise that it only fully considers the load characteristics and the operation environment, PoE can offer the advantage of simplified deployment and improve reliability.
A stable PoE system relies on the design, not luck.
