Totalizing

[ECSI 17]

Hi I have an Omron CJ1M-CPU12 PLC with analog inputs from a belt scale system. The 4-20 mA input gives me a present reading in tonnes per hour (TPH). This input is constantly changing with the amount of material going across the belt. I need to take this TPH reading and give the customer a readout in total tonnage. Do any of you have a good working formula or ladder logic to determine an accurate tonnage reading? Thanks in advance! Paul

[Jay Anthony 118]

Ummmh..... Off the top of my head, without checking the formula for accuracy: 1. Setup a one minute clock. 2. Every minute divide the analog input by 60. 3. Move result to a spare DM. 4. Add result to previous total. 5. Move total result to previous total location. 6. Previous total location represents current total tonnage. 7. For more accurate results, set up a one second clock and divide by 3600.