As we know, the standard TCP/IP network only reaches 100 meters. The PoE technology is designed basing on the TCP/IP which allows us to use single Ethernet cable to transmit both power and network. The maximum distance is also 100 meters. The network signal will start getting weak beyond 100 meters.
In some scenarios, we may need to run the cable longer than 100 meters for IP devices such as IP cameras, access points. The fiber optical cable is one of the solution, However we will have to deal with the power separately as the fiber optical cable is unable to carry the power. The PoE Extender (also name PoE repeater) is the equipment which can extend the PoE Network. The PoE Extender can repeat both power and data through cat5e/cat6 cable.
The PoE Extender usually has at least two ports. The PoE input and the PoE output. The PoE input will be connected to the Ethernet cable from PSEs, such as PoE injector, PoE Switch, or POE NVR. The PoE output will be linked to your IP devices(PDs) or PoE Extender. With daisy chain setup, multiple PoE Extenders will be chained together and form maximum 500 meters PoE network.
I guess you may wonder how the power works. There is no external PoE supply unit required for each PoE Extender. The PoE Extender will draw the power inline for own use and pass through the rest to the next powered device. While the power is transmitting through copper cable, part of the power will lose inline and convert to the heat. The longer the distance, the more power will be lost inline. Fortunately, the PoE/PoE+ employ DC48V in the system, the IP devices (Powered device) should have built-in PoE module which will regulate the higher voltage power to DC12V, even the part of the power lost inline, The remain power still can be regulated to DC12V. The below is the remain power vs the distance chart.
PoE NVR is the network video recorder with PoE switch integrated. The PoE NVR simplifies the system installation which provides both power and data to the PoE IP cameras. To extend the PoE connection beyond 100 meters, we also can use the daisy chain. Attached the PoE Extender to the end of the Ethernet cable, You will have another 100 meters distance. If you only need 150 meters distance, place the PoE Extender at the middle (75 meters) is the best practical setup.
The first thing to consider is still the power. Unlike PoE/PoE+ switch, the POE NVR may only supports PoE which output 14.4W. If the PoE NVR can’t supply the power after you add the PoE Extender, probably the power is not enough. There is always power lost inline. You can verify the power issue by using an external power supply to power the camera temporarily. If the camera can live stream video beyond 100 meters with external power supply unit. The possible cause is the power lost is too much inline. Making sure the connection is tight and it is the pure copper cable you have been used. The pure copper Ethernet cable is critical to long distance PoE extension. The pure copper cable can reduce the power lost inline as the resistance is small with pure copper cable. The cat6 cable may help improve the power transmission as well. Technically the cat6 cable is thicker than cat5e cable.
If the pure copper cable can’t settle down the issue, the PoE injector is another way to go. Most of the PoE NVRs employ DC48V power input and send to the front-end IP camera. While the power lost inline, the voltage will keep dropping. Once the remain voltage dropped down to DC37V or lower, your IP camera’s regulator will stop working. That is the essential about the power lost issue. Using the pure copper cable is able to reduce the power lost and keep the voltage higher than 37V. There is another simple way to achieve is we can use higher voltage power. According to IEEE802.3af/at, the voltage of PSE ranges from DC48V to DC57V. Some of the PoE injectors use DC54V to send to the front end IP camera because the DC54V can support longer distance PoE extension.
The PoE injector is a simple equipment to work with. There are two RJ45 ports, data in port and PoE out port, and one AC power input as well. The data port will be linked to the one of the PoE ports in the PoE NVR. The POE port is connected with the Ethernet cable leading to the PoE Extender. The PoE injector adds the power to the Ethernet cable. The RJ45 port on the PoE NVR only provides the data to the network link.
The surge is the issue while you are using the long range PoE Network. The surge may be picked up by the Ethernet cable and go forward to both camera and the PoE NVR. In practical installation, adding the PoE surge protectorcan improve the reliability of the IP camera system.