I would like some suggestions on how to end this problem. Do not use ferrites on DeviceNet cable. Look at Vol 1, Chapter 2-7.5 and make sure that the register setups in your CAN controller agree with what's in the Spec. Since the more stringent testing has been added to the compliance software tool, not all of the products that had a zero minor rev were re-tested, so the problem persists. weblink
Who's doing it? Answered by Ray Romito, DeviceNet Trainer, e-mail:
Did the problem go away? The options for this attribute are: 0 = fault & stop 1 = Ignore (warning optional) 2 = Vendor Specific This value can be fixed, or configurable. I have 2 vendors (Granville Phillips and MKS) that set up several different instances, but they don't work with the Allen Bradley Control Logix DeviceNet Scanner 1756-DNB. I suspect that the shield is not contiguous (T's, field-installed connectors and taps are likely suspects for the open circuit) or the shield/ DC Common/earth connection is faulty.
Are you using terminators? Thanks again Ken. The vendors followed up with firmware changes to their products. Allen Bradley Devicenet Power Supply Should this be cause for concern?
Q200) Troubleshooting (TS). Allen Bradley Devicenet Eds Files All I/O devices and serial connections are optically isolated. Check for loose wires at all DeviceNet connectors. http://odva.or.kr/devicenet_resources/DrDeviceNet/ts.htm The Rockwell Scanner verifies as best it can that the correct data is being transferred and applied to the logic engine. (Correct implementation decision) 3.
Any V- or shield connection to CAN_H or CAN_L will cause network instabilities. Allen Bradley Devicenet Bus Off Detected Have any of the devices been mis-wired in the past? Our hardware uses the non-isolated physical layer. For example, first, disconnect the Tx line from the 'C251 and tie it high or recessive.
Conformance testing does not flag this problem because there is no required response time to a given message. You did not mention the data rate. Allen Bradley Devicenet Cable Instance 2, consists of 3 bytes and returns Exception Status and Pressure in INT. Allen Bradley Devicenet Adapter If you are experience high error rates or network instabilities, you may want to check the system for additional shorts of the shield to ground or shield/V- to CAN_H or CAN_L.
If one were to build a diagnostic node using a CAN controller such as this, one could log these errors, but the offending frame is discarded before the interrupt, so one have a peek at these guys A DeviceNet cable that has a 600V rating on the jacket does mean that it can be routed in the same cable trays with respect to the NEC, however it does There is a separate software test tool that can be purchased from the ODVA to test the conformance of the EDS files. Many inspectors may be OK with this. Allen Bradley Devicenet Connectors
DeviceNet V- and SHIELD should be connected together at exactly one point. Contact Us - PLCS.net - Text - Top . There is typically a lot of vibration in an MCC, so wires that were originally snug can become loose. http://bsnux.com/allen-bradley/allen-bradley-devicenet-error-codes.html If the dust is conductive, then you definitely have a problem with open connectors in your wiring.
If the problem device is inserted to the network while the other devices are running, the problem device will power up properly and the other devices will continue to stay on Allen Bradley Devicenet Power Tap The device was operational with older versions of this tool, but the new release of the tool adopts a revision standard from ODVA that is new and does not allow a Note also that the V+ line will experience an equal and opposite drop.
The symptom is that for some period of time longer than #2, perhaps as long as 10 - 20 ms, a node will drive the bus dominant after a power up. Please offer comments, redirection or suggestions to clean up this issue quickly. andrewke1 View Public Profile Find More Posts by andrewke1 May 27th, 2008, 08:31 AM #3 OkiePC Lifetime Supporting Member Join Date: Mar 2005 Location: ENE of Nowhere Oklahoma Allen Bradley Devicenet Module By the way, the purpose for zero being invalid is because it is used as a wild card match for version checking.
There is no variable data in this discussion. see also Performance (PF) We installed several devices which time out regularly. Also, early versions of the Compliance Test Software did not check this.Sincethis. http://bsnux.com/allen-bradley/allen-bradley-devicenet-scanner-error-codes.html Typically, a hardware design problem causes power-up or power-down dominant glitches.
It's easy! regentb View Public Profile Find More Posts by regentb Jump to Live PLC Question and Answer Forum Bookmarks Twitter Reddit Digg del.icio.us StumbleUpon Google « Previous Thread | Next Thread » This is probably something we ought to allow to be set on a node-by-node basis on our (Rockwell) scanner products. Answered by Ray Romito, DeviceNet Trainer, e-mail:
Two 4-amp supplies on a non-segmented power bus exceeds the Class 2 limit. The nominal differential voltage for recessive bits is 0 V. There is apparently enough float on this unused input to periodically make the controller think it sees errors. Please try the request again.
Last edited by andrewke1; May 27th, 2008 at 07:36 AM. Are you saying that the vendor(s) have not provided the ability for the connection size attributes to be adjusted? BUSOFF attributes were also changed to cause nodes to reset. Answered by Nick Jones, System Architecture SIG, e-mail:
We've also seen bus off conditions caused by media problems such as: 1) Shorts in the cable system (either CAN H to CAN L or CAN signal to ground, etc) The