Things to Know About Power Over Ethernet Switch

Nowadays, with the rapid development of network technology, people are in need of a network technology that can support data transmission and power supply. The invention of power over Ethernet switch brings people a lot of conveniences because of their flexibility and reliability. And power over Ethernet switches have been applied in many applications in order to keep network at peak utilization. So what is power over Ethernet switch and how does it work? This post will give you the answer.

What Is Power Over Ethernet Switch and How Does It Work?

Power over Ethernet switch is also called PoE switch. PoE switch belongs to network switch or hub, it can not only transmit network data, but also supply power to connected devices over one Ethernet cable at the same time, which can greatly simplify the cabling process and cut costs. At the same time, PoE technology is applied in different devices, such as IP cameras, IP access points and voice over IP (VoIP) phones.

When PoE switch is connected with a PoE-Capable device, it can detect automatically the same devices that you have. Each of the spare wire pairs of PoE switch is treated as a single conductor and the electricity is injected onto the cable. And PoE switch can sometimes be transmitted on the data wires by applying a common-mode voltage to each pair. Because the twisted pair Ethernet cable uses differential signaling, the voltage doesn’t interfere with the data transmission.

PoE switch, power over Ethernet switch

Figure 1: How Does Power over Ethernet Switch Work?

Common Power Over Ethernet Types

According to different ports, power over Ethernet switch can be grouped into three common types, they are 8-port ,24-port and 48-port power over Ethernet switches. Different types differ in switching capacity, price and other aspects. For example, different PoE switches have different switching capacities and prices in FS (Figure 2). Different types of PoE switches also have different applications.

POE switch, power over Ethernet switch

Figure 2: Comparison of Different PoE Switch in FS

Confusing Questions About Power Over Ethernet Switch

1.What are the differences between PoE switches and normal switches?

They differ in reliability, function, cost and manipulation. Compared with normal switches which only support data transmission, power over Ethernet switch can support data transmission and power supply. Devices connected with power over Ethernet switch don’t need to perform power supply wiring, which can save costs and simplify the whole network management.

2.What is the differences between PoE and PoE+?

Firstly, one difference between PoE and PoE+ is the actual Institute of Electrical and Electronics Engineers (IEEE) standards themselves. PoE is 802.3af, while PoE+ is 802.3at. The maximum capacity of PoE can reach 25.5 w, while the maximum capacity of PoE+ can reach 35.4 w. Secondly, the maximum support current of PoE is 350mA, while PoE+ is 600mA.

3.Can I use PoE ports for non PoE devices?

Yes, you can. All PoE switches have auto-sensing PoE ports, which means that the PoE port will detect if the connected device is a PoE device or not. But it is very important for you to check whether your PoE device supports 802.3af or 802.3at. Because non-standard PoE switches don’t have auto-sensing PoE ports, which is more likely to damage the network port.

4.Do all Ethernet cables support  PoE?

Yes, nearly all Ethernet cables support PoE. PoE will work with existing cable, including Category 3, 5, 5e or 6.

Conclusion

It is without that power over Ethernet switches significantly improve the efficiency of network devices. After reading the whole passage, you may likely to have a general idea of PoE switches. FS provides different types of PoE switches for Ethernet PoE power supply and data communication. For more information, just reach us via sales@fs.com.

Related Articles

24 Port PoE Switch Power Consumption: 400W vs 600W

Gigabit PoE Switch vs Normal Switch

24 Port PoE Switch Power Consumption: 400W vs 600W

For buying gigabit PoE switch, we usually concern about port numbers. However, power consumption is often linked with port number to cater for different wattage requirement. Say small PoE switch 8 port may come with 130W or 250W for option. High port-density 48 port PoE switch may be available for up to 600W or even higher. A midsize 24 port PoE switch with appropriate power consumption will be a feasible solution for wide network applications. Since a power over Ethernet switch failing to provide enough power for Powered devices (PDs) leads to low performance or random drops. On the other hand, for cost-effective concern taking a 24 PoE switch with superfluous power budget will waste money. This article will introduce PoE switch power consumption and recommend 2 24 port PoE switch with different power consumption: 400W vs 600W for your reference.

24 Port PoE Switch Power Consumption Explanation
·24 Port PoE Switch Total Power Consumption

Power consumption of 24 port PoE managed switch refers to the max. total power the gigabit PoE switch enables to supply to all the PDs connected to it. That is, the total power wattage of all the connected PDs cannot exceed the power consumption of the 24 port PoE switch. So before deciding on how much a power consumption of PoE switch to buy, one must calculate the total power wattage of the PoE powered devices required to be used.

·24 Port PoE Switch Per Port Power Consumption

Another indispensable parameter of 24 PoE switch is the per PoE port power consumption, which is defined by PoE standard (IEEE802.3af) or PoE+ standard (IEEE802.3at). The PoE compliant switch supports up to 15.4W per port output power, while 12.95W input power is available for a PD due to transmission loss. Similarly the corresponding data of a PoE+ switch is 30W and 25.5W.

24 port PoE switch power consumption PoE standard

Figure 1: 24 port PoE switch power consumption PoE vs PoE+ standard comparison.

24 Port PoE Switch 400W vs 600W Power Consumption Comparison

24 port PoE switch 400W vs 600W power consumption apply to different level power wattage. Taking S1400-24T4F 400W and S1600-24T4F 600W PoE switch 24 port as example, let’s compare the scenario when fully load these two 24 port PoE gigabit switches with IP cameras. Divide 400W and 600W by 24 respectively, we get 16.67W and 25W per port power, which means the 600W over 400W power consumption 24 port PoE+ switch can support 24 higher-power IP cameras. The suggestion is: If you should use dozens of higher-power PDs, the 24 port PoE switch 600W would be a more secure and future-proofing choice.

S1400-24T4F 400W and S1600-24T4F 600W 24 port PoE switch power consumption

Figure 2: FS 24 port PoE switch power consumption 400W vs 600W model comparison.

24 Port PoE Switch 400W vs 600W Recommendation

Here we recommend the aforesaid advanced FS 24 PoE switches S1400-24T4F 400W and S1600-24T4F 600W for your reference. Compliant with IEEE 802.3af/at, these 24 port PoE gigabit switches can discern whether the PD is PoE or PoE+ standard for accurate power supply. This means FS 24 port PoE switch can supply up to 30W per port power, making it a natural fit for IP cameras, VoIP phones and wireless access points (APs).

In addition to high power consumption PoE capability, FS 24 port PoE managed switch features multiple port configuration to fit throughout different networks. The gigabit PoE switch centralizes 24 RJ45 auto-sensing 10/100/1000Mb PoE ports, 2 1Gb SFP ports and 2 SFP/RJ45 combo ports in a compact of 1RU form factor. The 24 PoE ports support up to 24 PDs simultaneously connected to the 24 port PoE switch within budget. The 2 SFP ports ensure optional fiber cabling and link aggregation of multiple switches, while the 2 SFP/RJ45 combo ports enhance network resiliency once again. In total one can enjoy a max. 1GbE density of 28 ports.

FS 24 port PoE switch application

Figure 3: Deploying 24 port PoE switch S1400-24T4F 400W and S1600-24T4F 600W for desktops, APs, IP cameras and IP phones in data center.

Conclusion

Power consumption is an important specification for choosing a good but cheap PoE switch. For choosing 400W vs 600W PoE switch 24 port, one should first figure out each PD’s rated wattage as well as all the devices’ total power budget. Then make sure a single IP phone won’t exceed the per port power consumption of the 24 port PoE switch, and the total wattage won’t exceed the max. power threshold of the 24 PoE switch. If S1400-24T4F 400W is not enough for current applications or future AP proliferation, then go for S1600-24T4F 600W model. All in all, whatever you choose, 24 port PoE switch price in FS.COM will always be competitive in the market.

Understanding Ports of Gigabit PoE Switch

Since the introduce of Power over Ethernet (PoE) technology, PoE LAN switch has become popular among wide users. However, newbies are usually confused with the multiple port configuration on gigabit PoE switch. Since there are already regular PoE Ethernet ports for powered devices (PDs), what are the function of other ports like console port, SFP/SFP+ port and combo port on gigabit PoE switch? This article will take 8 port PoE switch, 24 port PoE switch and 48 port PoE switch as example to illustrate multiple port for your reference.

Console Port on Gigabit PoE Switch

Like regular Ethernet switch, gigabit PoE switch often has one built-in serial console port, say FS S1130-8T2F 8 port PoE switch. It is the port for controlling and managing switch since there are no display device for a switch. Usually console port on gigabit PoE switch is an RJ45 receptacle. To connect a computer directly to the 8 port PoE switch, one should use dedicated rollover cable rather than Ethernet cable for connection.To use console port, you need physical access to the appliance. Therefore for terminals without serial console port, one should attach a corresponding adapter to the devices before cabling.

console port of 8 port gigabit PoE switch

Figure 1: A display of one console port on FS S1130-8T2F 8 port PoE switch for control.

RJ45 Port vs SFP Port on Gigabit PoE Switch

RJ45 port on gigabit PoE switch is the regular PoE port to achieve data and DC power transmission for PDs. It is an auto-sensing 10/100/1000Mb copper port supporting only Ethernet cable (Cat5e/6/6a/7) for connection. Thus RJ45 port connection is limited to 1G speed and 100m (330ft) short distance transmission. Then how about longer distance transmission scenario?

Different from RJ45 port, SFP port on gigabit PoE switch has the opt of both short and long reach. Why? The mini GBIC port has inherited the compatibility of either copper or optical SFP connection. Provided you employ the corresponding SFP module and cable on power over Ethernet switch. For long distance transmission, you should use fiber SFP modules with fiber patch cable for optical link. For short distance, you can opt to use RJ45 SFP module with copper network cable on gigabit PoE RJ45 switch for electrical link. Gigabit PoE switch often provides 2 SFP port for optical connection or uplink aggregation requirement, which enhances network adaption resiliency of PoE powered switch. For instance, S1400-24T4F 24 port PoE switch has 2 SFP ports reserved, which caters for fiber uplink to upper layer switch.

RJ45 Port vs SFP Port on Gigabit PoE Switch

Figure 2: A display of RJ45 ports vs SFP ports on FS gigabit PoE switch.

SFP+ Port on Gigabit PoE Switch

To illustrate SFP+ port on PoE Ethernet switch, we’ll take S1600-48T4S 48 port PoE switch as example. This 48 port PoE gigabit switch comes with 1 console port, 48 PoE+ RJ45 ports and 4 SFP+ ports. The 48 RJ45 ports are PoE ready to power on dozens of VoIP phones, IP cameras and wireless APs. The 4 SFP+ ports on gigabit PoE switch serves as uplink to connect 10G SFP switch for uplink aggregation.

S1600-48T4S 48 port gigabit PoE switch SFP+ port application

Figure 3: Deploying S1600-48T4S 48 port PoE switch as gigabit access switch to link 10G SFP switch via SFP+ ports, and connect PDs.

Combo Port on Gigabit PoE Switch

Though manufactures often clearly label combo ports on gigabit PoE switch for identification, many people don’t know its function. Take S1400-24T4F 24 port PoE switch as example, 2 combo ports are reserved on this 24 port PoE managed switch. The combo port compounds RJ45 and SFP front ends in one single interface, thus it supports either copper or optical SFP link. However, you cannot use these two physical accesses on PoE network switch simultaneously. That is, once you activate combo SFP port on gigabit PoE switch, you also disable the opposite copper port.

S1400-24T4F 24 port gigabit PoE switch combo port

Figure 4: A demonstration of combo ports on gigabit PoE switch: S1400-24T4F 24 port PoE switch from FS.COM.

Conclusion

To sum up, multiple ports on gigabit PoE switch owns different functionality, which enhances switching resiliency for different network cabling. RJ45 port on PoE powered switch is an normal one for copper link to PDs. SFP port of gigabit PoE switch provides options of fiber cabling or copper cabling due to fiber SFP module and RJ45 SFP module compatibility. 10G SFP+ port on 48 port PoE switch serves as uplink port for link aggregation in network layer. Combo port compounds RJ45 and SFP interface in one single fabric on gigabit PoE switch. So it helps to extend flexibility of physical access through the network. For 8/24/48 port cheap PoE switch buying, you can find decent offer here with optimal port configuration.