Signals
What this tool does
Scale a process value to 4–20 mA, 0–10 V, or 1–5 V, linear or square-root. This page says what the tool is for, in plain language. The working formula stays on the signed-in tool.
When to use it
Open Voltage and signal scaling when this is the job: Scale a process value to 4–20 mA, 0–10 V, or 1–5 V, linear or square-root. That is usually a loop check, a range change, or a signal that does not match the panel.
Step-by-step
- Open Voltage and signal scaling from the tool list.
- Fill Analog range, Transfer, Direction, LRV from the instrument, the drawing, or the job record. Use the unit shown beside each field.
- Fill the remaining fields the same way. Skip a field only when the screen marks it optional.
- Run Calculate when that control is on the page, then read every result row and any warning.
- Check the result against the site procedure and the manufacturer data before you change a range, a wire, a setpoint, or a weight.
- A free account can open this tool after signing in.
Inputs
- Analog range
- Choose the Analog range that matches the instrument, the drawing, or the job. Choices include 4–20 mA, 0–10 V, 1–5 V.
- Transfer
- Linear uses the span directly. Square root is for a differential-pressure flow signal.
- Direction
- Which way the conversion runs, from the engineering value to the signal or the other way.
- LRV
- Lower range value. The process reading at the bottom of the calibrated span.
- URV
- Upper range value. The process reading at the top of the calibrated span.
- Process value
- The live reading you are scaling, in the same engineering units as the range.
- Measured signal
- Measured signal is the value you read from the instrument, the drawing, or the job record.
- Engineering unit
- Engineering unit is a name or a note for this sheet. It does not change the check by itself.
Results
- Result
- The reported value for Voltage and signal scaling. Use the unit printed on that row.
- Warnings
- A warning means an entry is incomplete or outside what this tool will stand behind. Recheck the inputs and the site procedure.
Common mistakes
- Swapping the lower range and the upper range, or typing the live reading into a range field.
- Treating a square-root flow signal as if it were a linear span.
- Changing a range while a warning is still on the screen.
- Do not treat a result from Voltage and signal scaling as a substitute for the site procedure or the manufacturer data.
Standards references
These are the standards and public references named on this tool. Clause numbers appear only when the catalog already cites them.
- ISA-50.1 analog signal compatibility (4–20 mA, 1–5 V across 250 Ω, 0–10 V span)
- Bernoulli relation for differential-pressure flow (flow ∝ √ΔP)
Offline and access
This engine can run offline after the server has cached it for the signed-in account.
A free account can open this tool in the workspace.