Temp
What this tool does
IEC 60751 class A and B tolerance, plus 2-wire, 3-wire, and 4-wire lead error. 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 RTD tolerance class when this is the job: IEC 60751 class A and B tolerance, plus 2-wire, 3-wire, and 4-wire lead error. That is usually a sensor check, a cold-junction question, or a reading that does not match the gauge.
Step-by-step
- Open RTD tolerance class from the tool list.
- Fill Sensor, Class, Construction, Wiring 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.
- This help page is public. Opening the tool still requires a Pro session.
Inputs
- Sensor
- The resistance thermometer or thermocouple type named on the head.
- Class
- The tolerance class or the hazardous-area class named on the equipment.
- Construction
- Choose the Construction that matches the instrument, the drawing, or the job. Choices include Wire-wound, Film.
- Wiring
- Choose the Wiring that matches the instrument, the drawing, or the job. Choices include 2-wire, 3-wire, 4-wire.
- Temperature
- Temperature is the value you read from the instrument, the drawing, or the job record. Enter it in °C.
- One lead
- One lead is the value you read from the instrument, the drawing, or the job record. Enter it in Ω.
- Lead mismatch
- Lead mismatch is the value you read from the instrument, the drawing, or the job record. Enter it in Ω.
Results
- Result
- The reported value for RTD tolerance class. 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
- Picking the wrong sensor type, or leaving the cold junction at a temperature the terminal is not at.
- Reading resistance or millivolts as if they were already a temperature.
- Using a tolerance class that is not the class stamped on the sensor.
- Do not treat a result from RTD tolerance class 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.
- IEC 60751 industrial platinum resistance thermometers (Callendar–Van Dusen and tolerance classes AA, A, B, and C)
- Ohm's law on 2-wire, 3-wire, and 4-wire resistance measurement
Offline and access
This engine can run offline after the server has cached it for the signed-in account.
A free session can read this help page. The tool card shows the name and the short summary. Opening the tool requires Pro.