Pt100 vs Pt1000: Differences, Accuracy and Applications

What is the difference?

Both Pt100 and Pt1000 are platinum RTDs. The number refers to the nominal resistance at 0 °C:

Pt100: 100 Ω at 0 °C
Pt1000: 1000 Ω at 0 °C

They use the same platinum resistance principle and the same accuracy classes, but the higher resistance of Pt1000 changes how the sensor behaves in a real installation.

Why resistance matters

The resistance of the cable and connections adds to the measured resistance. For a Pt100, a small cable resistance is a larger percentage of the total signal. For a Pt1000, the same cable resistance is a smaller percentage, so a 2-wire Pt1000 can be more forgiving on short cable runs.

However, a higher resistance also means more self-heating for the same measurement current. Good transmitters and meters limit the excitation current, but self-heating can matter in still air or in small probes.

Comparison at a glance

Resistance: Pt100 = 100 Ω, Pt1000 = 1000 Ω at 0 °C
Cable sensitivity: Pt1000 is less affected by cable resistance
Self-heating: Pt1000 can generate more heat for the same current; check the instrument
Compatibility: Pt100 is the more common industrial standard; Pt1000 is common in HVAC, appliances and compact electronics
Accuracy: both are available in Class A, Class B and tighter tolerances

When to choose Pt100

General industrial probes and transmitters
Applications where the instrument is specified for Pt100
Long cable runs with a 3- or 4-wire connection
Replacement parts for existing Pt100 systems

See our Pt100 probe sensors and Pt100 transmitters.

When to choose Pt1000

HVAC and building controls
Appliance and compact electronic products
Short cable runs where a 2-wire connection is acceptable
Battery-powered or low-power devices with a suitable measurement circuit

Wiring and accuracy

For either element, the wiring method matters more than the nominal resistance:

2-wire: simplest, but cable resistance adds error
3-wire: compensates for cable resistance in industrial probes
4-wire: best accuracy for laboratory and long cables

If you need the best accuracy, choose a 4-wire Pt100 or Pt1000 and calibrate the complete probe.

Ordering tips

Tell us:

Element: Pt100 or Pt1000
Accuracy class: A, B, 1/3B or tighter
Wiring: 2, 3 or 4 wire
Probe diameter, length and thread
Cable length and insulation
Temperature range and environment

We supply Pt100/Pt1000 elements and complete probes. Contact us with your specification and we will recommend the closest standard or custom build.