EPL-ROUTER - Deutschmann Automation - #1

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THE RESULT MUST AGREE – BUS-TECHNOLOGY MADE BY DEUTSCHMANN!EPL-ROUTEREthernet Powerlink Router complying with the standards Ethernet Powerlink is a protocol extension to the Ethernet standard according to IEEE 802.3, in order to transfer real-time data in the time range of microseconds. It was developed considering standard conformity and it extends Ethernet by a mixed polling- and time slice-mechanism: With it the transfer of time-critical data is guaranteed within short isochronous cycles with configurable runtime performance as well as the time synchronization of all network nodes in the time range of sub-microseconds. The transfer of the less time-critical data traffic takes place in the reserved asynchronous channel. Current implementations of Ethernet Powerlink achieve cycle times of less then 200ìs and a time accuracy (Jitter) of less then 1ìs. Collisions on the Ethernet have to be avoided in order to guarantee the real-time. For that purpose the data transmission is controlled by means of a special node, the „Managing Node“ (MN). The other devices, the so-called „Controlled Nodes“ (CN) are only allowed to send if the MN asks them. Each cycle starts with a special telegram, the „Start of Cyclic“ (SoC). After that each node is prompted by the MN with a „Poll Request“ (PReq), whereon the CN replies with a „Poll Response“ (PRes). The PRes are sent by Ethernet-multicast. That way all others can also hear the response. A crosswise data-traffic between the CNs is possible. It is not necessary to poll every device in each cycle. Telegrams can be transferred by PDO and SDO.