thingstodo
Member
I would like to know if mapping Micrologix as ethernet I/O would replace the messaging that I am doing now. It would be a lot easier to understand and to troubleshoot! Micrologix don`t have produced/consumed tags
OK - here goes with the description ...
I have an L73 ControlLogix sending messages to 35 (yes, 35) Micrologix 1100 fixed IO PLCS, 10 input at 120V and 6 relay output. The details are below, but in general the gate is semi-inelligent and is told to open and to close. If communications are lost, the gate closes.
The communication is a pain to manage. This PLC is communicating to 10 other controlLogix for interlocks ... plus the 35 micrologix. 45 active messages obviously won't work. So they are timed, and modularized. The timeouts are set within the MSG instruction since 30 seconds (default) just won't work. I cringe whenever I have to change anything timing or messaging in this system.
One of the most annoying parts is to check that the MAC address of the micrologix matches what the Micrologix has stored. I'm sure that I have something not-quite-right, since my counters show a dozen messages failing this test every week or so. Each micrologix, once in a while, receives a message that is not intended for it. The messages go every 2.5 seconds and I get, like I mentioned, 6 - 12 messages that are wrong per week-ish (I don't check religiously any more). Just the Micrologix. Not the other ControlLogix.
More detail, if anyone is still reading ..
Each Micrologix has a local open and a local close pushbutton, as well as an open limit switch and a close limit switch. We have 2 power inputs, one for limits and one for the Open Solenoid. Only one output and it is energize to open, fail off (close). So communications loss, power loss, etc closes witha spring in the solenoid block and hydraulics with an accumulator
Each micrologix has one 16-bit word of interlocks, that must all be '1' in order for the OPEN commands to work, either locally or on the network.
The gates have a soft DCS/Maintenance switch (local control or remote)
a soft Enable/disable (safety enable by a supervisor)
a soft Auto/manual (gate opens and closes via a level loop or not)
The gates allow product to fall from a storage area onto a conveyor belt. So opening at the wrong time makes a big mess and wastes product.
If you made it all the way through that - congratulations!
OK - here goes with the description ...
I have an L73 ControlLogix sending messages to 35 (yes, 35) Micrologix 1100 fixed IO PLCS, 10 input at 120V and 6 relay output. The details are below, but in general the gate is semi-inelligent and is told to open and to close. If communications are lost, the gate closes.
The communication is a pain to manage. This PLC is communicating to 10 other controlLogix for interlocks ... plus the 35 micrologix. 45 active messages obviously won't work. So they are timed, and modularized. The timeouts are set within the MSG instruction since 30 seconds (default) just won't work. I cringe whenever I have to change anything timing or messaging in this system.
One of the most annoying parts is to check that the MAC address of the micrologix matches what the Micrologix has stored. I'm sure that I have something not-quite-right, since my counters show a dozen messages failing this test every week or so. Each micrologix, once in a while, receives a message that is not intended for it. The messages go every 2.5 seconds and I get, like I mentioned, 6 - 12 messages that are wrong per week-ish (I don't check religiously any more). Just the Micrologix. Not the other ControlLogix.
More detail, if anyone is still reading ..
Each Micrologix has a local open and a local close pushbutton, as well as an open limit switch and a close limit switch. We have 2 power inputs, one for limits and one for the Open Solenoid. Only one output and it is energize to open, fail off (close). So communications loss, power loss, etc closes witha spring in the solenoid block and hydraulics with an accumulator
Each micrologix has one 16-bit word of interlocks, that must all be '1' in order for the OPEN commands to work, either locally or on the network.
The gates have a soft DCS/Maintenance switch (local control or remote)
a soft Enable/disable (safety enable by a supervisor)
a soft Auto/manual (gate opens and closes via a level loop or not)
The gates allow product to fall from a storage area onto a conveyor belt. So opening at the wrong time makes a big mess and wastes product.
If you made it all the way through that - congratulations!