CALCULATORS / SENSORS AND INSTRUMENTATION

RTD excitation and readout calculator

Linear RTD approximation about zero Celsius; coefficient supplied.

sensors-rtd.napkin / editable

SCENARIO COMPARISON

Compare the numbers.

This source describes an analytical model. Its quantities and checks are the view.

Scenario	resistanceohm
	119.25
	95.4

All calculated quantities are listed with the inputs. Switch to Source to inspect the equations.

SCENARIOS / CALCULATED VALUESSAME SOURCE

Change an input to see the consequences.

resistance range example119.25 ohm✓ passes

BASELINE INPUTS

zeroResistance100 ohmcoefficient0.00385 K^-1temperatureRise50 K

CALCULATED

resistance119.25 ohm

Edits change the baseline source.

THE SOURCE

Edits below update the same model.

# RTD excitation and readout
# Scope: Linear RTD approximation about zero Celsius; coefficient supplied.
# Status: illustrative worked example; engineering review pending.
# Inputs are example values. Checks are editable example requirements, not standards.

zeroResistance = 100 ohm
coefficient = 0.00385 K^-1
temperatureRise = 50 K

resistance := zeroResistance*(1+coefficient*temperatureRise) [ohm]

check resistance range example: resistance <= 150 ohm

scenario alternative: zeroResistance = 80 ohm

Calculated from your source · not saved

Baseline · Baseline

resistance range example119.25 ohm ✓ passes

alternative · alternative

resistance range example95.40 ohm ✓ passes

Illustrative first-order example. Checks are editable requirements, not design standards. The broader topic may require additional equations, data, and validation.

Formula and units

This example uses the following equations. Input names and units match the editable source above.

resistance: resistance = zeroResistance*(1+coefficient*temperatureRise) [ohm]

Original worked example

These are the baseline values in the downloadable source. Edits above let you test your own values.

Given

zero resistance: 100 ohm
coefficient: 0.00385 K^-1
temperature rise: 50 K

Calculated

resistance: 119.25 ohm

Assumptions and limits

Linear RTD approximation about zero Celsius; coefficient supplied.

The requirement checks use the limits written in this example. Passing a check does not establish that the model covers every load, material behavior, or operating condition in a real design.

Download this .napkin example ↓

Take it further with your agent

Napkin keeps the inputs, equations, checks and assumptions together in one study. Your agent sets it up; you change the numbers.

Try with Claude ↗

codex 'Use Napkin (https://napkin.engineering/mcp, or the local Napkin plugin) to build a study: RTD excitation and readout. Inputs: RTD curve; excitation; wiring resistance; gain. Outputs: temperature estimate; lead-error screening. Model scope: Measurement chains with explicit noise, bandwidth and calibration. Read napkin_capabilities and the current snapshot. Ask me for the values that matter, label assumptions with units, author .napkin source, validate it and apply it with napkin_source using the current revision, then open the study. Add checks for the limits I supply. Keep unsupported analyses explicit.'

Claude needs the Napkin connector; Codex needs the Napkin plugin. Set up your agent ↗

The broader study

The topic brief below describes the broader scope. The worked example above states the particular calculation it implements.

Inputs: RTD curve, excitation, wiring resistance, gain
Outputs: temperature estimate, lead-error screening
Modes: calculate, compare, sweep
Drawing: Signal-chain and error plots

EXECUTABLE WORKED EXAMPLE · FIRST-ORDER MODEL · CHECK THE SCOPE & ASSUMPTIONS