PIDTune vs Plutocalc+ Water

PID Tuner uses the IMC (Internal Model Control) method to calculate PID tuning parameters. I’ve tried a lot of tuning methods over the years and have found this one to be the best. The app is written for the iPad to show all the information on one page. The program calculates: PID Parameters: Controller Gain (Kc) Integral Time (Ti) Derivative Time (Td) For process types First Order with Dead Time (FO) Second Order with Dead Time (SO) Integrating or Long Time Constant with Dead Time (I) For controller types Parallel (non-interacting) c(s) = Kc (1 + 1/(Ti s) + Td s) Series (interacting) c(s) = Kc (Ti s + 1)/(Ti s)(Td s + 1) For controller modes PID PI You can either enter the process gain (Kp) directly or enter the changes in the controlled virable (CV) and manipulated variable (MV). Tuning aggression is adjusted using the slider to set the closed loop time constant to the process time constant ratio (λ/Ƭ). The closed loop time constant (λ) is the time the controller is expected to reach set point (plus the dead time (ϴ)). Setting the closed loop time constant to process time constant ratio (λ/Ƭ) to 1.0 will make the MV change to its final value and allow the process to settle out to the setpoint. Setting (λ/Ƭ) greater than 1.0 will give a slower responce. Setting (λ/Ƭ) less than 1.0 will cause the MV to make a larger change and then reduce to its final value. Tight tuning would be to set the close loop time constant to the dead time. Use the Integrating Process type (Ƭ = ∞) for both integrating processes or processes with long time constants. These processes use the maximum slope as the process gain. Tuning aggression for these processes is determined by setting the closed loop time constant to the dead time ratio (λ/ϴ). Once again, setting the closed loop time constat to the dead time gives tight control. References: “Probably the test simple PID tuning rules in the World,” Sigurd Skogestad, Jounal of Process Control, July 3, 2001 “Consider the generalized IMC-PID method for PID controller tuning of time-delay processes,” Y. Lee, S. Park, M. Lee, Hydrocarbon Processing, January 2006

Plutocalc is the most complete and popular problem solver suite for water treatment, wastewater, hydraulics, environmental chemistry and unit conversions. Plutocalc+ is a premium version of the free Plutocalc packed some extras. For iOS, only the premium version is available. Features: - 103 solvers - 2670+ different calculations - Self explanatory diagrams - Internal databases for chemicals and standards - Results as you type, nothing is faster than that! - Multiple languages: English, Portuguese and Spanish - Available for multiple platforms - 100% offline, no data connection required - Advertisement free NOTE: If after the update the program loads to a blank screen, just reinstall to fix. Solver list: Conversions - Angle - Area - Conductivity and resistivity - Density and concentration - Energy - Flow - mass - Flow - volumetric - Flux and rates - Forces - Hardness in water - Length - Mass - Power - Pressure - Speed - Temperature - Time - Volume Geometry - Buffer tank capacity - Cylinder volume - Cone volume - Cube volume - Circle properties (radius, diameter, perimeter and area) - Horizontal cylindrical tank volume - Triangle properties with sides/angles determination - Municipal plants flow estimation - Nominal pipe sizes and wall thickness - Sieve sizes according - Rainfall volume Energy and power - Head loss in pipes - Open channels or partially filled pipes - Orifice plates with incompressible fluids - Parshall flumes flow measurement - Rectangular flumes flow measurement - Flow adjustment for dosing/metering pumps - Pump power and energy consumption - Blowers and compressors power and energy consumption - Mixing velocity gradient - Reynolds number and speed Contaminants - Boiler water quality and blowdown - Periodic table of elements with oxidation states - Ionic Balance and Conductivity - CO2 conductivity in pure water - TOC, COD and KMnO4 relations - Langlier Saturation Index - LSI - Ryznar Stability Index - RSI - Silt Density Index - SDI - Modified Fouling Index - MFI - Sludge Volume Index - SVI Solutions - Chemical dosing flow, mass and concentrations - Dry chemical dosing flow - Chemical solutions density database - Water properties (viscosity, density) - Gases properties (density and molecular weight) - Oxygen solubility in water - Multiple streams blending - Specific gravity, Baumé, Brix and API relations Adsorption and Ion Exchange - Sorption/Exchange capacity - Empty Bed Contact Time and BV/h - Ion Exchange regeneration - Ion Exchange softener design Filters and membranes (Reverse Osmosis, Ultrafiltration and Nanofiltration) - Cylindrical filter rate and speed - Microfiltration / Ultrafiltration comparison and normalization - Reverse Osmosis membranes and datasheets comparison - Reverse Osmosis plant normalization and performance comparison - Reverse Osmosis / NF skid design - Recovery - Recovery for membranes in series - Normalized permeability - Granular media head loss (sand, resins, anthracite, carbon and custom) - Granular media backwash expansion rate Reactions - pH equilibrium for: Ammonia, Sulfates, Boric Acid, Sulfides, Silicic Acid, Phosphates and Nitrous Acid - Equilibrium for Carbonates with temperature dependence - Disinfection with Chlorine, Chlorine Dioxide, Chloramines and Ozone - Disinfection with Chlorine for Giardia Cysts - Disinfection with UV - Iron oxidation and precipitation - Manganese oxidation and precipitation - Sludge from chemicals - Food-to-microorganisms ratio - F/M - Ultimate BOD Clarifiers - Surface loading rate - circular - Surface loading rate - rectangular - Hydraulic retention time - HRT - Solids retention time - SRT - Solids loading rate - Volumetric solids loading rate - Return activated sludge recycle - RAS - Discrete sedimentation - Sludge concentration and mass - Sludge age Finance - Ordinary annuity - Annuity due - Compound annual growth rate - CAGR - Interest rate conversions - Simple interest