Power over Ethernet has been widely applied for smart homes or businesses, various IP devices benefits from PoE because of its convenience, stability, and flexibility an so on, such as the commonly used devices like IP cameras, wireless access point, access control,etc. With the popularity of PoE and IoT, these kinds of devices also show its influence in industrial fields or other applications that required to deploy at outdoor or harsh environment, so did those PoE devices for power networking infrastructure set up, like PoE switches, PoE injector, and some other devices that of great use to realize effective transmission of power and network for the edge connected IP devices. In fact, utilizing PoE technology for outdoor and harsh environment deployment however call for a deeply and more considerate thinking before actual implement. This article intends to elaborate into somethings truly worthy knowing.
Why Use PoE for Outdoor Harsh Deployment?
PoE, in a manner of speaking, re-defines the cabling method of power networking infrastructure meeting the needs of low voltage IP devices setup for the reason that it enables power to be transmitted together with data simultaneously over a single Ethernet cable. Take the IP cameras for an example, traditionally, the installers have to find extra AC outlet or run wiring close to the cameras, while taking advantage of PoE in the connection from the main control room to the camera’s mounting point, local AC outlets are able to be eliminated as power and data are transmitted at the same time over one cable from the PSE to the PDs. In this way, the installation and cabling of the system are bound to be easier and more flexible, furthermore, saving time and money investment. And because of this, it would seem like that PoE technology is to be a natural choice for networking deployment at outdoor or in the harsh environment. You should aware that refer to these applications, power issue generally is one of the common difficulty, because it is more difficult to wire or obtain a present AC outlet. Additionally, the cost for cabling is likely to be higher due to deployment distance and cable material.
How to Know the Harsh is Really Harsh?
Some people, especially as to the end-users, probably still confused about the definition of harsh environment. Therefore, at the beginning, not mention the outdoor environment, how harsh can be recognized to be harsh. You should be aware that the most significant difference between commercial grade devices and hardened grade devices is the resistance capability for fluctuating temperature and elements. Commercial grade PoE devices, such as PoE switches, can only meet network deployed at and operated under a good condition where suppose clean enough, with a stable and controllable operating temperature, few influenced by bad weathers, and so on. In short, the environment has lower potential risks for non-human damages. That being said, if it is hard to guarantee that the devices stay at environment out of risks of elements like extreme temperature, humidity, surges, even dust or dirt, basically, even it is an indoor installment, you’d better consider to a harsh networking deployment. In the following, let’s go deeply into the detail information concerning about network deployed at outdoor or in the harsh environment.
Challenges and Problems Under Outdoor Harsh Environment
Some common challenges or problems will be triggered due to the elements generated in the outdoor or harsh PoE deployment, and PoE devices or the whole system come with a higher potential to experience risks that may threat the utility, stability as well as usage life.
Extreme temperature should be first challenge influencing all the electrical devices, especially when the devices required to be operating under hot summer, constrained space with high temperature, or other alike environment, because if the temperature exceed the range that devices can bear, problems come naturally. Furthermore, you can’t deny the fact that the higher the temperature rises and the more sever problems explode. Extreme temperature generate great harm to the whole devices thoroughly. No matter the components or the housing of the devices come with a range of operating temperature, when temperature higher than the range, the heat collected inside the housing is likely regarded as a boom that may explode at any moment, or if lower than the range, the devices generally can’t be powered on under a ultra low temperature. Just think about have your mobile phone shut down in a sudden in extremely cold winter. Then low temperature is to blame for this situation.
Outdoor deployment a high possibility to experience all kinds of surges, although most surges won’t cause harm to the devices themselves, these devices place at a fixed locations, and these locations generally with few covers, that being said, power surges, or even shocks, as well as vibrations are able to damage the devices directly, and such damages may result in an irreversible failure to the devices, or the whole system. Not to say those industrial applications, these applications require a demanding industrial grade devices to meet the needs, otherwise, you may encounter dilemmas like device failure, frequent maintenance, property loss or safety accident and so on.
As mentioned earlier, not only outdoor deployment call for attention, some indoor deployment in the harsh environment also shows its challenge to the installation and system stability. Don’t underestimate the influence of dust and dirt, such two issues can make the functionality and usage life discount dramatically. Moreover, water ingress is another common issue that can easily found at some indoor mounting point, such as the ceilings or water pipes.
How to Solve the Problems and Get An Advanced Protective System?
For the starter, picking up suitable devices that can work well under harsh environment is a crucial fundamental to realize a stable and safe connection. Common devices feature commercial grade can only meet the needs for applications that can be protected in a safe, clean condition, or where can keep the a relative stable operating temperature. It is high recommended to focus on devices that specially designed for outdoor or industrial uses, because these kinds of the products are supposed to have a great resistance to water, dust and dirt, extreme temperature and surges or some bad weathers thanks to their high quality components, rugged metal housing, outstanding IP rating, and worthy-trust surge protection. Despite the higher price, outdoor rated and industrial grade products should be always the first consideration in our mind.
Apart from the devices, the connection part is often overlook in practice, and there are quite a certain quantity of cases ended with a broken system because of an inadequate consideration on the connection part. Cable takes in a heavy part, while many installers or end-users have little awareness to pay more attention or investment on the cable. Or sometime just because lacking of basic knowledge about cable types.
There are different types of cable, when choose cable for a networking system adopts Ethernet cable as connection media, pure copper shielded cable is the optimal option, this sort of cable intends to help reduce power and signal loss in the transmission, especially for those deployments requiring a long range transmission for the reason that the longer the distance is, the more the power and signal lose. Besides, shielded cable comes with a stronger capability to stand for various damages under harsh environment, such as rains, dust, dirt, etc. For the fiber optic connection that utilize fiber optic cable should follow the same thinking, that being said, a strong enough cable is the answer, such as armored fiber optic cable that designed for outdoor only or indoor&outdoor applications, because this type of cables grant a better ability to withstand harsh environment. To be honest, even if the cable features excellent resistance to harsh environment, you’d better use waterproof and dust-proof enclose to protect the cable when it is applied in the direct-buried type installation in the long term.
Not only cable is the most significant connection part, cable gland also need to take into consideration. Pick out those devices equips with high IP rated cable gland, or for some special applications, you are able to select the rugged metal one made from aluminum, which offer a more secure and reliable connection.
All the above methods start from the physical devices and tools, to achieve an advanced protective system, correct installation is of dramatically importance. Not a possible to guarantee the stability of the system if a wrong or insufficient installation is implemented. As a rule of thumb, majority of installers fail to aware that the outdoor rated products need to reply on the assistance of installment tools, for example, only using hands to screw the cable gland isn’t enough, a wrench can boost the reliability optimally. There are some other protective measures function as an addition, for instance, adding a surge protector at both sides of the electronic devices.
What Devices Can Meet Outdoor & Harsh Networking Deployment?
Have learned numerous knowledge about outdoor and harsh PoE networking deployment. Next, naturally is to concern on how to build a PoE networking system and how to choose devices. Product features like IP67 or higher waterproof rated, wider operating temperature range from–40 to 75°C, durable metal housing probably meet the outdoor and harsh deployment mostly. In the process of purchase, only to focus on products with the keywords of outdoor, rugged, hardened, industrial, waterproof.
For different applications and to satisfy specific requirements, there are different types of outdoor PoE devices available in the market for your option. PoE system is simply formed with two parts, namely PSE(Power Sourcing Equipment) and PD(Powered Device). Below list some common used PoE PSE that come with all the demanding features discussed above.
PoE injector commonly used to help integrate Non-PoE with PoE. It is a kind of PoE PSE that can inject power to a exiting networking system, if you plan to install PoE-compliant device at the edge, but you only have network switch or Ethernet switch without PoE technology, PoE injector can help supply PoE to the edge PoE devices over single cable with no need to buy a new switch to replace the original one. In addition, PoE injectors complied with IEEE802.3 at/bt is effective solution to solve power supply issue for those power hungry IP devices, because if the main control PSE, such as PoE switch that comply with IEEE802.3af standard, only providing a maximum of 15.3W, while the connecting edge devices ask for a higher input power wattage, in this situation, PoE injector can inject high power PoE+ or PoE++ to the system with no damage to the original data.
Some outdoor PoE injector support a wide power input range, and equipped with power booster. Therefore, PoE injector can boost or fluctuate the voltage and output a stable voltage, so that not only the standard PoE device can make use of PoE power solution, some non-standard devices with low voltage or high voltage can receive power and network over single cable despite voltage drop issue to some extent.
To sum up, PoE injectors is convenient way that allows you to integrate PoE, obtain high power PoE+ or PoE++, and acquire stable PoE as well.
In fact, as mentioned at the first beginning, outdoor deployment sometimes face with longer deployment distance. As to PoE technology, due to power drop and signal loss, Ethernet cable endows a transmission limit at 100m(328ft). As a result, deployment distance over this range demand PoE or Ethernet extension solution to reach a long range transmission. In the following, some choices are present.
PoE powered switches, also called PoE pass through switches, are similar with common PoE switches, but there are some difference between these two devices. PoE powered switches are a kind of switches that can be powered by PoE PSE, like PoE switches and PoE injectors, and PoE can be pass through and then transmit to the connected edge devices(PoE or Non-PoE), which is unlike the common PoE switches that requiring extra AC power, PoE powered switches save local AC outlet so as to ease installation difficulty and improve deployment flexibility. Thanks to this feature, it is useful networking expansion solution for applications that installed at places that is hard to find AC outlet or outdoor harsh environment. Certainly, it also support local AC power, and in this case, it simply acts as a common PoE switch that is specially designed for outdoor uses.
To overcome long range transmission and get an extended PoE or Ethernet, PoE extenders has been widely used. PoE extenders also adopt PoE powered technology, which help repeat PoE and extend to reach a longer distance for the connected edge devices. Generally speaking, for those support daisy chain, it can realize a maximum of 500m PoE transmission, as one unit add 100m(328ft). Some are with two PoE output and complied with IEEE802.3bt standard, which can accept 90W Max. input power from the PSE, and automatically allocate the power to their two PoE outputs, each one can supply 30W Max. output power. Just like the PoE powered switch, PoE extenders with two outputs can be a convenient network port expansion tool for adding one more IP devices by re-using the existing Ethernet cabling.
Although reply on PoE extension solution, the transmission distance can’t meet the need for ultra long range deployment that counts with kilometer. Furthermore, Ethernet connection, especially over long distance hard to realize a high speed network due to signal loss. Fiber optics show its advantages of long distance, high bandwidth, and low latency. To utilize fiber with PoE for networking, you can turn to fiber media converters and fiber PoE switches.
Fiber optics and copper Ethernet rely on different media to transmit signal, the former uses light and the later uses copper, consequently, to mix fiber and PoE or Ethernet, signal conversion tool is required. Fiber media converter is the quickest way to start simple point to point fiber optic link. In general, a pair of media converters is required, one at the back end, the other at the edge end. Apart from media converter, SFP transceivers and fiber optic cable are needed to accomplish the fiber optic link. Whereas, there are quite common to find PoE switches that equipped with SFP slot, that means one media converter is built in the switch, thus only one media converter is required.
Fiber media converter is easy to use and economic choice, for for applications with a demands for installing multiple devices around the same points, PoE switch with SFP is the better choice. Just like we talked just now, it is a PoE switch with built-in SFP slot, there are multiple PoE ports for various IP devices.
