Palletizer cell, 1769-L36ERM, remote rack is a 1734 AENTR out on the wrap station, fed from its own 24V supply at the wrapper. When the wrapper gets locked out for a jam the rack loses power and the whole controller goes to major fault, OK red, so the palletizer stops with it. Both machines down for one jam.
Controller Properties, Major Faults says Type 03 Code 16, I/O connection failure, and it names the AENTR. We tried a bigger 24V supply and a shorter run, no change, and it isn't really a power thing anyway, the rack is off on purpose when they lock out.
Is the L36ERM faulty? Other lines here drop remote racks all the time and just get a yellow triangle. Could someone explain what's set differently on this one that turns a rack going dark into a major fault?
Not faulty. What changed since it last did the yellow triangle thing, or has it always done this? And open the AENTR in the tree, Module Properties, Connection tab, and read me the checkboxes. There's one in there about a major fault.
Always done it as far as anyone knows, this cell came in 2021 from an OEM. Connection tab: RPI 20ms, Inhibit Module unticked, Major Fault On Controller If Connection Fails While in Run Mode is ticked. Photo attached. Use Unicast unticked too.
That box. Nobody ever means to tick it.
OG
Bill's right. That checkbox is exactly what it says, the adapter dropping becomes a controller major fault instead of a faulted module in the tree. An OEM ticks it when losing that rack should hard stop the machine, which for a wrapper is defensible, so ask them before you change it. If the palletizer should carry on, untick it, download, and handle the rack state in logic instead: GSV Module, the AENTR's name, EntryStatus into a DINT, the upper four bits tell you the state, 16#4000 is running if I remember right. Interlock the palletizer on that. There's a decent writeup on reading module status this way: https://plctr.com/advanced-troubleshooting-techniques-for-plc-systems/
Talked to the OEM this morning first, they said the box was a default in their template, no reason. Unticked it, downloaded at the shift changeover, then had the wrapper locked out on purpose. AENTR went yellow triangle, palletizer kept running. Put the GSV in and a light on the screen for the wrap rack.
So it was that one checkbox on the AENTR, Major Fault On Controller If Connection Fails, ticked in an OEM template. Unticked, GSV in, and the palletizer stays up.
The bit I didn't expect: 16#4000 when running, yes, but I got 16#4001 for a second on power up, not sure what the 1 is.
Thanks priya87 and billr.
Same box bit us on a filler in 2019. Still don't know who ticked ours.
OG