Industrial Ethernet

COMMON OSTACLES TO SING ETHERNET ON THE FACTORY FLOOR HICH CAN NO E OERCOME

Deterinis Ethernet networks regulate how devices gain access to the channel for message transmission through a concept known as Carrier Sense MultipleAccess Collision Detect CSMA/CD. All devices listen to the network, and may try to send a message if they do not sense any other traffic on the chan-nel. owever, if more than one device tries to access the channel at the same time, a collision occurs. All of the devices backoff and will try again arandom amount of time later. This is different than many other industrial networks which use arbitration schemes so critical messages receive priorityin reaching their destination. CSMA/CD makes Ethernet inherently non-deterministic because it cant be known exactly how many times a collision may occur. hile this may seem to preclude the use of Ethernet to deliver control-related information, there are two factors that need to belooked at Throughput The network user needs to understand if what they reallyneed is determinism the ability to calculate a repeatable amount of time in which the message will be delivered or throughput having the mes- sage reliably delivered within a certain time frame, even if that time is vari- able within that range. The wire speeds of Ethernet are often orders of magnitude faster than other industrial networks, meaning that even with multiple collisions there is an extremely high likelihood that Ethernet will provide much quicker delivery of control related messages. Switching technology hen devices are connected to a repeater hub,those devices are all part of a collision domain, vying for channel access.sing a switching hub eliminates collisions by creating dedicated band-width between the device and the switch. hile there is still a latency variable for the switch to forward the message, using only switches for network design can satisfy a large amount of applications that do require determinism. radCounications
TM IndustrialEternet DIN Rail-Mounted Switc Lack of an oen alication layer Ethernet, even when combined with TCP/IP, still does not provide the complete specification for network transmission, as it does not call out an application layer analogous to the language the network speaks. nlike in an office where a handful of application layers FTP, SMTP are support-ed by most computing devices, most vendors of factory automation equipment have implemented their own application layer, precluding interoper-ability. ecently standards for open application layers have evolved, including Modbus TCP, and Ethernet/IP, which utilies the application layer fromDeviceNet. As vendors begin to adopt these open applications layers for use in their devices, the issue of multi-vendor interoperability will rapidlydecrease. urailit in arsh Enirnents Standard Ethernet cabling and connectors manufacturer were designed with an office environment in mind, and arent intended to withstand the environmentalconditions commonly found on a factory floor or in harsh commercial applications. The BradConnectivity
TM line of Ethernet products overcomes thisobstacle by combining standard - connection technology with the industrially proven form-factor, or by utiliing industry-standard Micro-ChangeM connection technology. The result is a lineup of products designed to preserve the integrity of your data transmission even in theharshest settings. Specific benefits include Sealing against environmental contaminants BradConnectivity
TM industrial Ethernet connectorsprovide protection from ingress of typical factory haards such as water, oil, dirt and dust, which would corrupt a standard - connection. Protection against the effects of vibration hile commercial - connectors can expect a longlife when mounted in a communications closet, they are not designed to withstand any level of vibration. For the BradConnectivity
TM form-factor threaded style, the overmolding process andaddition of the mini connector on the cordsets, isolates the gold contacts from the effects of vibration, significantly increasing the life of the product. The Micro-Change M form-factor is an inherently vibration-resistant connection technology. Provides a secure robust connection In the industrial world it is not uncommon for maintenancepersonnel and operators to come in contact with the cabling system. Our connectors, with inte- grated strain relief, make it nearly impossible for the connection to be broken when force is applied to the cable. Performs in electrically noisy conditions Motors, drives, transmitters are all elements found on thefactory floor, and all generate EMI Electro-Magnetic Interference. BradConnectivity
TM shieldedcordsets and receptacles enhance data integrity in this environment while P acketed cables protect against oxidation.

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