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01 Increasing the system

01 Increasing the system availability by means of integrated surge protection and shield current monitoring Power over Ethernet supports higher system availability In an increasingly networked world, it is essential to have direct access to the data for all processes. Power over Ethernet supports the easy integration of this data in existing networks. Using the new PoE injectors, the user saves a great deal of time during installation, while simultaneously protecting both the connected devices and data transmission against surge voltage, different potentials and EMI. As a manufacturer-independent IEEE standard, Power over Ethernet (PoE) has established itself in industrial applications for more than ten years now. Cabling effort can be considerably reduced using PoE technology. In addition, networking is more flexible and the streamlined PoE cabling lowers installation costs. Distributed network devices, which, for example, are located outside of buildings, require only one cable for data and power transmission. The devices to be connected include access points, access controls, and applications with camera surveillance to which an ever-increasing importance is attached. Ideal for powering Voice over IP phones (VoIP), Power over Ethernet has long since proven itself in the office sector. The PoE technology distinguishes itself by powering devices via the data cable. The power required for this purpose is negotiated electrically between the consumer – the powered device (PD) – and the supplier – the power sourcing equipment (PSE). Supply voltage is then provided with a transmission speed of up to 100 Mbps (mode AUTOMATION Author: Bernd Rosenbaum, Product Manager in the area of Communication Interfaces, Phoenix Contact Electronics GmbH, Bad Pyrmont, Germany 03 The cable shielding is connected easily without tools, providing strain relief at the same time 02 PoE injectors are available with RJ45, screw, Push-in and IDC fast connection technology 14 WORLD OF INDUSTRIES 8/2018

B) via the unused wires of the eight-wire cabling. Alternatively, the so-called phantom power with a maximum data rate of 1 Gbps can be activated in a modulated way using the data cables (mode A). The mode will be negotiated of own accord but, if required, its setting can also be fixed using DIP switches. The PSE may consist of a multiport PoE switch or a PoE injector as a stand-alone solution. Internal power supply unit with electrical isolation Just in time for the Hannover Messe 2018, Phoenix Contact presents its new PoE injectors for different performance classes. With a supply of up to 30 Watt, these devices meet the IEEE 802.3 af (15.4 W) and 802.3 at (30 W) standards. Although the upcoming IEEE 802.3 bt standard still needs to be adopted, the POE injectors have been designed in such a way to meet future requirements as well (as an option). For example, the 60 Watt components enable powerful PTZ (pan/tilt/zoom) cameras to be supplied with power, which often have integrated infrared heating to avoid fogging of the glass surface. To this end, there is more power required than provided by the existing IEEE 802.3 PoE standard up to 30 W. In addition to the different performance classes up to 60 W, the PoE injectors are characterized by a wide operating temperature range from -40 to 75°C, ensuring a diverse range of applications. Flexibility regarding the device supply is ensured by the redundant input voltage range from 18 V DC … 57 V DC. It is therefore possible to use 24 V DC and 48 V DC power supply units. The internal supply unit offers electrical isolation to avoid short circuits on the PoE supply cable. This protects the PoE injector as well as upstream power supply units and other components within the supply segment from being damaged due to a short circuit between PoE-carrying data wires and against cable shielding, leading to significant cost savings. Not to mention the fact that the use of electrically isolated power supply units is mandatory for numerous applications. Integrated protection against coupled voltages For the first time, the PoE injectors are provided with an optional, integrated surge protection. This is due to the fact that Ethernet interfaces operate with low signal levels at high frequencies. As a result, they are particularly sensitive to surge voltages which can lead to the destruction of expensive network components. Especially with regard to cabling across several buildings or control cabinets, the devices may be adversely affected by the coupling of voltages. The surge protection integrated in the injectors meets the DIN EN 61643-21 standard, IEC test classification C2. The PoE-carrying port at the field side is intended to be used as surge protection interface. All eight signal paths are protected by this solution. The new PoE injectors also convince through their patented shield current monitoring. If the installation is characterized by different potential references, this may cause equalization currents flowing through the cable shielding. This may result in damage to expensive equipment and lead to a standstill of the entire production process. To counteract this, the PoE injectors INJ 2000 offer simple diagnostic options. Existing equalization currents or currents coupled on the PoE-carrying cable are measured and indicated using an LED. It lights up red if the cable shield current exceeds 30 mA. This shows the user that a general grounding issue exists in their entire installation. Individual control cabinets or building parts might have been connected improperly with regard to their potentials or there is still a high risk of electromagnetic influences on the cable during installation. Integrated patch panel for different connection technologies As a further feature, the PoE injectors offer an integrated patch panel function for the first time. In addition to the commonly used RJ45 New Ethernet patch panel for fast cabling The connection technologies and protective mechanisms of PoE injectors are also used for the eight new Ethernet patch panels from Phoenix Contact that are available in two function groups. The passive termination boards allow quick and easy connection between the field and control cabinet cabling. Apart from the standard modules with compact design, the new patch panels offer integrated surge protection. This protects the connected terminal devices and ensures a high degree of system availability. This also applies to the additional shield current monitoring, as grounding problems are indicated using an LED. Various connection technologies (e.g., IDC, screw and Push-in) make the connection of the field cable more convenient. With strain relief assured at the same time, the cable shielding is connected without tools, saving in this way a great deal of time. socket for both Ethernet ports, terminal technologies are provided to connect the PoE-carrying field cable. Thanks to the easy connection of the cable to the injector, it is possible to do without the complex installation of an RJ45 connector with special tools. Similarly, it is no longer necessary to place a separate patch panel using a patch connection cable. This saves costs and space on the DIN rail. Patented cable shielding contacting with strain relief The PoE injectors INJ 2000 with patch panel function also offer a new type of shield contacting. The cable shielding can be connected without tools, providing strain relief at the same time. A shield contact spring presses the cable with the braided shield folded back over the cable sheath against a contact surface located directly on the conducting path of the circuit board. For this purpose, the cable is placed into the slot and the spring sheet pressed with the finger until it locks into place in the housing. In this way, the cable shielding covers a large surface and the strain relief for the cable reaches a value of up to 50 Newton. To release the connection, the lock only needs to be levered up with a screwdriver. If the user closes the housing cover with slight pressure after cable connection, the shield contacting will not open even during extreme vibration. The shielding is securely and directly connected to ground potential via the DIN rail. It is therefore possible to discharge all interferences occurring on the cable shielding. Summary The new PoE injectors from Phoenix Contact supply devices in the field with data and power up to 60 Watt via just one cable. New functions such as integrated surge protection and shield current monitoring ensure trouble-free operation of the application, while the built-in patch panel cuts installation costs and saves space in the control cabinet. Thanks to the wide operating temperature range and the high transmission rate of up to 1 Gbps, these devices are ideally suited to supply surveillance cameras. Photographs: Phoenix Contact WORLD OF INDUSTRIES 8/2018 15