Removing ONS, OSR, and OSF Logic

We have a vendor that loves ONS logic. It does ok as long as things run as expected. Well we all no nothing runs as expected for very long. If the machine is stopped mid cycle things lock up and they need to be reset bit by bit. I am kind of being lazy but more so wanting to save time. Is there any quick fix to remove OSR and OSF locic other than manualy reprogramming it bit by bit rung by rung? I do know there is a place and time for ONS logic, dont get me wrong, but not in just about every rung. I have used Latch/Unlatch logic with ONS logic in some situations.

Removing them all quickly could be a recipe for disaster. Going rung by rung gives you a chance to examine the logic to determine if a ONS is necessary or not. If you just removed them all in one go, you might cause as many problems as you solve. You could do a search for ONS instructions to quickly navigate between them all in the program, but I would still take the time to examine the rung and determine if removing the ONS could cause issues. Take special care on rungs with latch bits and math instructions.

I agree with LoganB.

you must look at each rung to see what the purpose of the instruction was in the logic.

james

I agree with the above posters. Also keep in mind that if there is an HMI on this system, sometimes bits are latched in the HMI and then unlatched in the PLC (for example, pushbuttons) which can be overlooked rewriting OTL/OTU logic.