Morning all. Bagging line here has a Point I/O drop on a 1734 AENTR with eight cards behind it, and four or five times a shift the whole drop goes yellow triangle in the tree and comes back a few seconds later. I look after the network side and Rockwell I/O is not my ground at all, so bear with me.
I've been over my own end first. Checked the port counters on the switch and they're clean, no late collisions, nothing in the log, and I've pinged the adapter continuously for two days without losing a packet.
Then I went and stood in front of the adapter and the display is showing 1734. That's all I could catch before it changed. None of the fault code lists I can find have a 1734 in them, so I think I'm reading the wrong thing entirely.
Is 1734 a code, and if it isn't, what is that display meant to be telling me?
That's the catalogue number going past, not a code. Video it on your phone and play it back slow.
Filmed it and stepped through it frame by frame. It goes 1734-AENTR, then FW 4.011, then 192.168.2.31, then back to 1734-AENTR and round again.
What I missed standing there is the timing. It reaches the end of the address and starts over about every twenty seconds, all day, whether the drop is faulted at that moment or not.
Twenty seconds could be the link renegotiating. Look at the switch port the adapter lands on and see whether somebody has forced it to 100 full while the AENTR is left on autonegotiate. A duplex mismatch does not always leave anything on the counters, and the I/O connection times out every time the port bounces.
Port was forced, you were right about that much. 100 full on the switch, auto on the adapter. Set both ends to auto and left it an hour.
Still doing it. Same twenty seconds, same yellow triangles, and now the counters are all at zero and I've nothing left on my side of the fence. No luck at all.
Then stop looking at the network. That display only runs the catalogue number, the revision and the address at power up. If you are watching it start over every twenty seconds, the adapter isn't scrolling, it is rebooting, and a rebooting adapter drops every connection behind it. There are your triangles.
So measure. Meter on the 24V right at the adapter terminals with min and max capture switched on, leave it through a run of whatever big thing sits near that panel, then read the minimum off it. What the controller reports while that is happening is covered here: https://plctr.com/allen-bradley-plc-i-o-faults-causes-solutions/
Meter on the terminals overnight on min max and the minimum came back 17.8V. Watched it sag this morning every time the dust extractor contactor pulls in, roughly every twenty seconds while the bagger runs.
The adapter, the field wiring and both extractor coils all feed off one small 24V supply somebody fitted years ago. It was never the network. It was browning out and running its display sequence again from the top, and I was reading the catalogue number off a module that had just come back up.
Adapter is on the 1606 control supply now, own pair. Two shifts, no triangles. I still can't say why it ran a whole year first. Thanks boris_h, and northbay for telling me what I was looking at.
Marking solved. That display is a status line, not a fault code.
plctr.com team