The switchboard was installed at least 10years ago by someone else who really took pride in their work as you can see from the image on the left, and overtime there were changes to the programing that were never recorded and field devices had been bypassed.
We programmed the PLC to the original diagrams and then we installed it and had to commission the system from scratch and change the program to suit new operation requirements.
There were a lot of man hours put into this both from us and the Lemon tree feedlot staff, I think somewhere we spent somewhere in the vicinity of 60hrs on it including programing and commissioning. I think my quote was for 38hrs so we definitely lost money on this one, but it was worth it in the end to have the system operating better than the day it was first installed.
Top Image - the old PLC covered in Rodent droppings and spider webs.
Second Image - The main Mill SBD with the new PLC installed in the commissioning stage.