Pt100 vs Pt1000: Resistance, Sensitivity and Application Differences

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Temperature Measurement
Pt100 vs Pt1000: Resistance, Sensitivity and Application Differences

The Pt100 vs Pt1000 question comes down to nominal resistance at 0°C: 100 Ω versus 1000 Ω at ice point.

Both share the same platinum material, the same temperature range, and the same temperature coefficient. The practical differences appear in sensitivity, lead wire error, self-heating, and transmitter compatibility.

This guide covers every Pt100 vs Pt1000 difference that matters for sensor selection, wiring, and measurement accuracy.

100 Ω vs 1000 Ω at 0°C 0.385 vs 3.85 Ω/°C Lead Wire Error Self-Heating Effect

In the Pt100 vs Pt1000 comparison: both use platinum, IEC 60751, TCR 0.00385 Ω/Ω/°C. The Pt1000 is ten times more sensitive. The same 1 Ω lead wire resistance causes 2.6°C error in a Pt100 but only 0.26°C in a Pt1000.

Pt100 vs Pt1000: Why the Resistance Value Matters

Hello! Today we are comparing Pt100 vs Pt1000 RTD sensors. These are the two most common platinum RTD types in industrial and commercial temperature measurement. They look identical on the outside and measure temperature by the same physical principle. But their different base resistance values create real differences in sensitivity, lead wire error, self-heating, and instrument compatibility that affect which one belongs in your application.
Pt100 vs Pt1000

Both Pt100 and Pt1000 are platinum resistance thermometers (RTDs). Platinum resistance increases linearly with temperature.

At 0°C, the Pt100 = 100 Ω and the Pt1000 = 1000 Ω. This 10:1 ratio is the only electrical difference between them.

Three consequences follow from this ratio: the sensitivity difference, the lead wire error difference, and the self-heating difference. Each affects which sensor is appropriate for your application. Click any term to expand.

Sensitivity: Sensitivity is the change in resistance per degree Celsius. For a Pt100 this is 0.385 Ω/°C. For a Pt1000 it is 3.85 Ω/°C. The Pt1000 produces ten times more signal per degree, which is easier for the measurement electronics to resolve. This makes the Pt1000 more immune to electrical noise on long cable runs and a better choice for low-cost transmitters or direct microcontroller input where the ADC has limited resolution.
Lead Wire Error: Every meter of copper lead wire adds resistance to the measured value. The same length of 0.5 mm² copper wire adds the same resistance in ohms regardless of whether it is connected to a Pt100 or a Pt1000. But that resistance represents a much larger fraction of the total Pt100 signal. A 1 Ω lead resistance causes approximately 2.6°C of error in a Pt100 (2-wire configuration). The same 1 Ω lead causes only 0.26°C error in a Pt1000. This is why Pt1000 sensors are preferred for 2-wire installations with long cable runs.
Self-Heating: When an excitation current flows through the RTD, it dissipates power as heat (P = I² × R). A Pt1000 with the same excitation current as a Pt100 dissipates ten times more power. To keep self-heating error below 0.1°C, the excitation current for a Pt1000 must be reduced to approximately one third of the current used for a Pt100. Most modern transmitters set excitation current automatically based on the configured sensor type. Always verify the excitation current specification when selecting a transmitter.
100 Ω
Pt100 resistance at 0°C (ice point) per IEC 60751
1000 Ω
Pt1000 resistance at 0°C -- exactly 10 times higher than Pt100
0.00385
Temperature coefficient of resistance (TCR) in Ω/Ω/°C -- identical for both sensors
10×
The Pt1000 is ten times more sensitive and ten times less affected by lead wire resistance
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Pt100 vs Pt1000 Resistance at Key Temperatures

The resistance of a platinum RTD follows the Callendar-Van Dusen equation. For practical engineering purposes, the linear approximation is accurate to within 0.5% over the range 0 to 400°C:

RTD Resistance Formula (linear approximation)
R(T) = R₀ × (1 + α × T)
R(T): resistance at temperature T (Ω)
R₀: nominal resistance at 0°C (100 Ω for Pt100, 1000 Ω for Pt1000)
α: temperature coefficient of resistance = 0.00385 Ω/Ω/°C (IEC 60751)
T: temperature in °C

At 100°C: Pt100 = 100 × (1 + 0.00385 × 100) = 138.5 Ω
At 100°C: Pt1000 = 1000 × (1 + 0.00385 × 100) = 1385 Ω
TemperaturePt100 Resistance (Ω)Pt1000 Resistance (Ω)Difference
minus 200°C18.52185.2Pt1000 is 10× higher -- always
minus 50°C80.31803.1Pt1000 is 10× higher -- always
0°C (ice point)100.001000.0Nominal reference values per IEC 60751
25°C109.731097.3Difference is 9.73 Ω vs 97.3 Ω from 0°C
100°C138.511385.138.51 Ω change vs 385.1 Ω change from 0°C
200°C175.861758.675.86 Ω change vs 758.6 Ω change from 0°C
400°C247.092470.9Pt100 usable to 600°C; Pt1000 typically to 400°C
600°C313.713137.1Pt100 preferred above 400°C with suitable transmitter
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Pt100 vs Pt1000: Full Comparison

ParameterPt100Pt1000
Nominal resistance at 0°C100 Ω1000 Ω
Sensitivity0.385 Ω/°C3.85 Ω/°C
Temperature rangeminus 200°C to 600°C (wire-wound); minus 50°C to 150°C (thin-film)minus 200°C to 400°C typical
TCR (IEC 60751)0.00385 Ω/Ω/°C0.00385 Ω/Ω/°C -- identical
Lead wire error (2-wire, 1 Ω lead)Approximately 2.6°C errorApproximately 0.26°C error -- 10× better
Recommended wiring3-wire or 4-wire for accuracy2-wire acceptable for most applications
Self-heating per mA excitationLower (P = I² × 100)Higher (P = I² × 1000) -- needs lower excitation current
Noise immunityLower signal per degree -- more sensitive to interferenceHigher signal per degree -- better noise immunity
Industrial transmitter supportUniversal -- all process transmitters support Pt100Good -- most modern transmitters support Pt1000; check older instruments
Common applicationsIndustrial process control, oil and gas, power generation, food processingHVAC, refrigeration, automotive, building automation, machine building

Lead Wire Error: The Most Critical Pt100 vs Pt1000 Difference

The lead wire resistance error is the main reason to choose Pt1000 over Pt100 in certain installations. Copper wires have a resistance of approximately 0.017 Ω per metre per mm² cross section.

A 10-metre cable with 0.5 mm² conductors adds 0.34 Ω per wire, totalling 0.68 Ω in a 2-wire circuit.

Lead Error Calculation (2-wire configuration)
Temperature error = R_lead / sensitivity
R_lead: total lead resistance in both wires (Ω)
Sensitivity: 0.385 Ω/°C for Pt100, 3.85 Ω/°C for Pt1000

Example: 10 m cable, 0.5 mm² conductors, R_lead = 0.68 Ω
Pt100 error = 0.68 / 0.385 = 1.77°C
Pt1000 error = 0.68 / 3.85 = 0.18°C

This is why the Pt100 needs 3-wire or 4-wire connections for accuracy. For the Pt1000, 0.68 Ω is only 0.068% of total sensor resistance, making 2-wire error acceptable for most applications.

See the RTD sensor connections guide for 2-wire, 3-wire, and 4-wire wiring diagrams.

A 3-wire Pt100 is more accurate than a 2-wire Pt1000 only when the three wires are identical in resistance. If the cable is damaged or a connector has a poor crimp on just one wire, the 3-wire compensation is invalid and the error can be worse than a simple 2-wire Pt1000. For critical measurements, a 4-wire Pt100 remains the most accurate configuration available.

Pt100 vs Pt1000 Resistance and Lead Error Calculator

RTD Resistance and Lead Wire Error Calculator
Calculate resistance at any temperature and lead error for Pt100 vs Pt1000
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When to Choose Pt100 vs Pt1000

Choose Pt100 when:

You need highest accuracy with 3 or 4-wire wiring. You are measuring above 400°C. Your transmitter supports only Pt100. Your application is standard industrial process control.

See the RTD working principle guide for Pt100 construction details.

Choose Pt1000 when:

You are using a 2-wire configuration with cable runs longer than 5 metres. Your application is HVAC, refrigeration, automotive, or building automation.

Also suited to electronics with limited ADC resolution and battery-powered loggers where low excitation current matters.

Pt100 in 4-wire for highest accuracy

Laboratory and high-precision process applications use 4-wire Pt100. The 4-wire connection eliminates all lead resistance effects.

This combination remains the gold standard for precision temperature measurement. See the Pt100 calibration guide and the temperature transmitter calibration guide.

Replacing one with the other

A Pt100 and a Pt1000 cannot be interchanged without reconfiguring the transmitter.

A Pt1000 installed on a Pt100 transmitter reads ten times higher than expected. Always match sensor type to transmitter configuration. See the RTD and thermocouple guide.

Watch: Pt100 vs Pt1000 RTD Sensor Differences Explained

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Pt100 vs Pt1000 Questions

What is the main difference between Pt100 and Pt1000?
Nominal resistance at 0°C: Pt100 = 100 Ω, Pt1000 = 1000 Ω. Both follow IEC 60751 (TCR 0.00385 Ω/Ω/°C). The Pt1000 is ten times more sensitive and ten times less affected by lead resistance.
Can I replace a Pt100 with a Pt1000 without changing anything else?
No. The transmitter must be reconfigured to match the new sensor type. A Pt1000 installed on a transmitter configured for Pt100 will read a resistance 10 times higher and report a grossly incorrect temperature.
Why is the Pt1000 better for 2-wire installations?
The same 1 Ω lead resistance causes 2.6°C error in a Pt100 but only 0.26°C in a Pt1000. This makes 2-wire Pt1000 installations acceptable for many applications.
Do Pt100 and Pt1000 have the same temperature range?
The Pt100 wire-wound type covers minus 200°C to 600°C. The Pt1000 is typically rated to 400°C. For measurements above 400°C, a Pt100 with a 3 or 4-wire configuration is preferred.
Which has better noise immunity, Pt100 or Pt1000?
The Pt1000 produces 3.85 Ω/°C versus 0.385 Ω/°C for the Pt100. The larger signal is less affected by electromagnetic interference on long cable runs.

External References

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What We Learn Today

  • Pt100 vs Pt1000: both are platinum RTDs following IEC 60751 with identical TCR (0.00385 Ω/Ω/°C). The only electrical difference is the nominal resistance at 0°C -- 100 Ω vs 1000 Ω.
  • Sensitivity: Pt100 = 0.385 Ω/°C, Pt1000 = 3.85 Ω/°C. The Pt1000 produces ten times more signal per degree.
  • Lead wire error (2-wire): the same 1 Ω of lead causes 2.6°C error in a Pt100 but only 0.26°C in a Pt1000. Use Pt1000 for long 2-wire cable runs.
  • Use Pt100 (3-wire or 4-wire) for highest accuracy industrial process control and for temperatures above 400°C.
  • Use Pt1000 for HVAC, building automation, refrigeration, and 2-wire long-cable installations where lead error is a concern.
  • Never replace a Pt100 with a Pt1000 (or vice versa) without reconfiguring the transmitter. The resistance values are ten times apart and the output will be completely wrong.
“Pt100 vs Pt1000 is not a question of better or worse. It is a question of which one fits your wiring configuration, your cable length, your temperature range, and your transmitter.”

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