PCFL-TOTAL help

[Marshy 0]

Hi, We have a flow meter that gives us an analog flow rate. I'm trying to use the PCFL-Total function to totalise the amount of water pumped. I've read chapter 142 in the Ladder Logic User Guide that describes the function but was hoping for some kind of example on how to program it? So far I've set the solution interval to 1000 and I get a resulting sum when running the function. The main problem I have at the moment is how to reset it. When I set the 5th bit in the input word it doesn't reset to 0? If anyone has used this function before and can point me in the right direction I'd be greatly appreciated. Many thanks