Convert 4-20 mA, 0-10 V, or PLC raw counts into engineering units using standard linear scaling. Use it for pressure transmitters, temperature inputs, tank level, flow, speed references, HMIs, and PLC logic.
This page is useful when the raw value looks correct but the displayed engineering value is wrong, shifted, clamped, reversed, or scaled to the wrong span.
Analog issues usually start at the field device, wiring, card configuration, raw value, scaling math, and HMI display. Work through the system instead of changing numbers blindly.
Start with the PLC system, confirm the input path, scale the raw value, then verify electrical delivery if needed.
Use this calculator to convert current, voltage, or raw PLC counts into real engineering values such as PSI, °F, inches, flow, level, speed, or pressure.
It follows the standard linear scaling method commonly used in ladder logic, structured text, HMI math, and controller-side signal conditioning.
Typical pressure transmitter example scaled into PSI.
Example speed command or feedback signal scaled into RPM.
Allen-Bradley-style raw count example scaled into temperature.
Save analog scaling setups, reload previous inputs, and reuse common PLC signal ranges.
This calculator uses standard linear interpolation. It is intended for normal analog scaling applications and does not include filtering, sensor non-linearity, card calibration offsets, underrange/overrange fault thresholds, broken-wire diagnostics, or module-specific behavior.
Use this when a pressure transmitter, temperature input, level sensor, linear transducer, or analog speed reference needs to be converted into a meaningful machine value.
It also helps verify whether scaling errors are happening in the PLC, HMI, sensor setup, or analog module configuration.
If the displayed analog value is wrong, do not only change the scale numbers. Check the raw value, wiring, card setup, engineering span, and HMI formatting.
Use this when the analog point or field signal may not be reaching the controller correctly.
Use this when long wiring runs or weak delivered voltage may be affecting the signal or device.
Use this if raw values are missing, stale, or not reaching the HMI or higher-level system.
Analog scaling problems are usually caused by a mismatch between the device span, card configuration, raw count range, PLC math, and HMI display. This tool helps isolate the math side of that problem.
A 4-20 mA pressure transmitter may be physically wired and reading correctly, but the PLC may be scaling it as 0-20 mA or using the wrong engineering span.
That can make a real 150 PSI pressure display as the wrong value even though the transmitter and wiring are fine.
If you are scaling analog devices in a PLC, HMI, or controls upgrade and want help with logic, commissioning, or troubleshooting, use the support path below.