Saturation Calculator

Saturation Calculator is an engineering tool that fits measurement data approaching a constant value to a first-order response model and estimates the final steady-state value. Enter elapsed time and measured values directly on your iPhone at the plant floor, beside equipment, at a test site, or in the laboratory. Results can be checked on-site without bringing a computer, transferring measurements to a spreadsheet, or waiting until you return to your desk. TYPICAL USE CASES • Checking stabilization after equipment startup or warm-up • Evaluating temperature, pressure, flow, or sensor-output responses • Observing how a measurement approaches a stable value after a setting change • Estimating stable values during equipment inspection and commissioning • Analyzing response measurements in research and development • Reviewing measurement trends in production and quality control • Performing quick analysis where using a computer is impractical KEY FEATURES • Estimate the steady-state value from elapsed-time and measured-value data • Select seconds, minutes, or hours • Automatically handle increasing and decreasing responses • Fit all entered data to a first-order model using nonlinear least squares • Display clear guidance when the data cannot produce a stable fit • Perform calculations directly on the iPhone The free version calculates the Steady-State Value from three measurement points. A one-time purchase unlocks the Full Version with: • From 3 to 100 data points • 95% Response Time • Time Constant • 98% Response Time • Coefficient of determination (R²) • A graph of measured data and the fitted curve • Interactive inspection of the predicted value at any time on the graph The calculation uses the following first-order model: y(t) = y∞ + (y0 − y∞) exp(−t / τ) The measured value at t = 0 is used as the initial value. This app is intended for analyzing data that can reasonably be approximated by a first-order saturation response. It may not be suitable for every physical process and is not intended to be the sole basis for safety-critical decisions. Entered measurements and calculation results are not stored permanently on the device.