Processor is a SLC 5/05. Fairly new at programming and we are going to slowly automate some of the manul operations at the plant. This is what i wrote up to automatically transfer oil into our tank until we hit a specified weight. we have 2 tanks to transfer in to, 6010 and 6020, and 2 tanks to transfer from, 2000 and 2001.

Here is what i have so far. Its very basic but i believe everything is in order. Let me know if you see anything obvious. I always post up what i think is the perfect program and then alaric or mickey says, what if you did this and suddenly the clouds lift. If its full of errors then just tell me to try again but if it looks ok but might need some attention, please let me know what you think.

Looks good for the basics, may want to consider the usual Valve Failed to Open, Valve Failed to Close, Pump Failed to start, Pump Failed to stop logic that is common in these application.

You don't mention how you are measuring your delivered oil, load cells, meter etc.. One thing that you may have to consider is over shoot. In most cases the system has some few seconds of lag. So, you reach setpoint and stop the pump, close the valve etc... By the time these actions occur, you have surpassed your set point by some amount. If the system always overshoots the same quantity, it's easy to correct. If the material delivered varies in viscosity, line size, pump capacity etc... Then, you will have to come up with a more complicated system to accommodate the over shoot.

If you can give more details about the equipment used, we can possibly give you a few pointers.

Also, in my opinion your ladder needs a LOT more descriptions. You should have a comment on each ladder explaining exactly what that ladder is doing. It will aide us in understanding your logic, and a year down the road, when you have to modify your logic, you will be glad you did. Otherwise, you will have to try and decide what you were thinking when you wrote the logic.