POINT I/O 1756 ENTR2 errors

[Corben 2]

Hi everyone, i needd some advice to resolve problems i encounter. I have a control logix 1756L62 BACKPLANE 1756A13 with 2 ethernet Cards -1st is 1756 ENT2 (for supervisory) and 2nd is 1756 EN2TR (for point I/O 1734 AENTR with 1734IB8 & 1734OW4). after those cards i have 1x1756 IF8 & 4x1756IB32 & 4x1756OB32. On the tab "module info" of 1756 EN2TR everything is correct but on the tab "network" i see: - Ring faults detected:2 - Status: Rapid fault/restore cycles. So i went to check the tab "port conf" both enable / both Auto negociate / port 1 full duplex in 100Mbps / port 2 half duplex 100Mbps - port diagnostic of port 1: Mac receive erros: 8 605 089 - port diagnostic of port 2: Single collision: 8 715 018 & multiple collision 7734 in my advanced network conf of 1756 i set Supervisor precedence: 2 / beacon interval 400 / Beacon time out: 1960 Module definition is Electronic keying: disable / Connection: None(no ther choice) / Time sync & motion in my advanced network conf of 1734AENTR i set Module definition is Electronic keying: compatible module / Connection: Rack optimisation So the tab "port conf" both enable / both Auto negociate / both full duplex in 100Mbps - port diagnostic of port 1: Mac Transmit erros: 52 373 - port diagnostic of port 2: Alignement errors 2 / FCS Errors 5 I tried to change ethernet cables but nothing change i changed beacon settings but nothing. somethinfg doesn't match but what? i will continue to search & try but if someone has an idea i'm open Thanks in advanced

[Ken Roach 194]

Those FCS and Collision errors very strongly suggest that there's something wrong with the wiring. I realize you've changed the cables, but those are plain indications of miswired pairs or extreme noise problems. Have you validated the cables with a cable tester ?

[Corben 2]

Yesss, i found :-2 in the manual: EtherNet/IP Embedded Switch Technology, they talk about the rapid ring fault issue and they give 4 causes : 1- 5 intentional disconnections/reconnections 2- A duplex mismatch between two connected devices 3- Electromagnetic noise on the network 4- Unstable physical connections, such as intermittent connectors so i changed again my 2 cables in the ring ( i have just 1 device on it) like you suggest ken, but nothing changed. I know Electromagnetic noise canot be the reason because i work in one technical framework and it's very clean. So the last solution was the duplex mismatch, and i realised that the both devices on the ring are not set the same. 1734 AENTR port 2 was set full duplex & 1756EN2TR was set half. I changed settings , i cleared faults, reset counter and the Link 2 status indicator switched on and no more ring fault. thanks anyway.

[Ken Roach 194]

Thank you very much for posting that detailed followup. I'm glad to hear you got it working !