ความแตกต่างระหว่างเซ็นเซอร์ Pt100 และ Pt1000

This article introduces platinum sensors in resistance temperature detectors (RTD), especially the differences between Pt100 and Pt1000. Including their nominal resistance, Wzp, Abb, datasheet, characteristic curves and the advantages of 3 wire and 4 wire in different applications. Focus is on the factors to consider when selecting sensors, such as linearity, operating temperature range, lead effect and standardization issues.

PT100/PT1000 Sensor Temperature Sesnor Probe 3*15mm Thermocouple Contr

PT100 PT1000 Surface Mount Thermal Resistor Temperature Sensor Probe

PT100 PT1000 Sensor with Thread Probe High Temperature Cable

Many industries use RTDs to measure temperature, and the sensors in most of these devices are Pt100 or Pt1000. These two temperature sensors have similar characteristics, but the difference in their nominal resistance may determine which one you choose for your application.

เครื่องตรวจจับอุณหภูมิความต้านทาน (RTD) are also called resistance thermometers. They have become popular temperature measurement devices due to their reliability, accuracy, versatility, repeatability and easy installation.

The basic principle of RTD is that its wire sensor (made of metal with known resistance) changes its resistance value as the temperature increases or decreases. Although resistance thermometers have certain limitations, including a maximum measurement temperature of approximately 1,100°F (600องศาเซลเซียส), overall they are an ideal temperature measurement solution for a wide range of product designs.

difference between a Pt100 and a Pt1000 sensor

Why Use Platinum Sensors?

Pt100 and Pt1000 Platinum is commonly used in sensors, particularly for temperature measurement, due to its exceptional stability, high resistance to oxidation, a wide operating temperature range, and a very predictable change in electrical resistance with temperature, making it ideal for precise and reliable readings in demanding environments.
The sensing wire in an RTD can be made of nickel, copper, or tungsten, but platinum (พ.ต) is by far the most commonly used metal. It is more expensive than other materials, but platinum has several properties that make it particularly suitable for temperature measurement, รวมทั้ง:

Almost linear temperature-resistance relationship
High resistivity (59 Ω/cmf compared to 36 Ω/cmf for nickel)
No decrease in resistance over time
Excellent stability
Very good chemical passivity
High resistance to contamination

Difference between Pt100 and Pt1000 sensors?
ความแตกต่างที่สำคัญระหว่างเซ็นเซอร์ Pt100 และ Pt1000 คือความต้านทานที่ระบุที่ 0°C, โดยที่ Pt100 มีแนวต้าน 100 โอห์ม และ Pt1000 มีความต้านทานเท่ากับ 1000 โอห์ม, หมายความว่า Pt1000 มีความต้านทานสูงกว่าอย่างเห็นได้ชัด, ทำให้เหมาะสำหรับการใช้งานที่ต้องการการวัดอุณหภูมิที่แม่นยำโดยมีผลกระทบน้อยที่สุดจากความต้านทานของลวดตะกั่ว, โดยเฉพาะในการกำหนดค่าวงจร 2 สาย; while a Pt100 is often preferred for 3 หรือ 4 wire circuits due to its lower resistance value which can be more affected by lead wire resistance. Key points about Pt100 and Pt1000 sensors: Resistance at 0°C: Pt100 has 100 โอห์ม, Pt1000 has 1000 โอห์ม. Application suitability: Pt1000 is better for applications with long lead wires or 2-wire circuits due to its higher resistance, while Pt100 is often used in 3 หรือ 4 wire circuits to compensate for lead wire resistance.
Accuracy in small temperature changes:
Pt1000 is generally considered more accurate for small temperature changes due to its larger resistance change per degree temperature change.
Both are Platinum Resistance Thermometers (RTD):
Both sensors use platinum as the sensing element and operate based on the principle that the resistance of platinum changes with temperature.
Among platinum RTD sensors, Pt100 and Pt1000 are the most common. The nominal resistance of a Pt100 sensor at ice point (0องศาเซลเซียส) is 100Ω. The nominal resistance of a Pt1000 sensor at 0°C is 1,000Ω. Both have the same characteristic curve linearity, operating temperature range, and response time. The temperature coefficient of resistance is also the same.

อย่างไรก็ตาม, due to the difference in nominal resistance, a Pt1000 sensor can read 10 times higher than a Pt100 sensor. This difference becomes apparent when comparing 2-wire configurations where lead wire measurement errors apply. ตัวอย่างเช่น, a Pt100 might have a measurement error of +1.0°C, while a Pt1000 might have a measurement error of +0.1°C in the same design.
How to Choose the Right Platinum Sensor

Both types of sensors work well in 3-wire and 4-wire configurations, where the additional wires and connectors compensate for the effects of lead wire resistance on temperature measurement. Both types are also similarly priced. อย่างไรก็ตาม, Pt100 sensors are more popular than Pt1000 for the following reasons:

Pt100 sensors are available in both wirewound and thin film constructions, giving users choice and flexibility. Pt1000 RTDs are almost always thin film.

Because Pt100 RTDs are so widely used across industries, they are compatible with a wide range of instruments and processes.

So why would someone choose a Pt1000 sensor? A larger nominal resistance offers clear advantages in the following situations:

Pt1000 sensors work better in 2-wire configurations and with longer lead lengths. The fewer wires and the longer they are, the more resistance is added to the reading, causing inaccuracies. The larger nominal resistance of the Pt1000 sensor can compensate for these added errors.

Pt1000 sensors are better suited for battery-powered applications. Sensors with higher nominal resistance use less current and therefore require less power to operate. Lower power consumption extends battery life and maintenance intervals, reducing downtime and costs.

Because Pt1000 sensors consume less power, they also self-heat less. This means fewer reading errors due to above-ambient temperatures.

โดยทั่วไป, Pt100 temperature sensors are more commonly found in process applications, while Pt1000 sensors are used in refrigeration, ความร้อน, ventilation, เกี่ยวกับยานยนต์, and machine manufacturing applications.
Replacing RTDs: A Note on Industry Standards

RTDs are easy to replace, but it’s not a matter of simply swapping one out for another. An issue that users must be aware of when replacing existing Pt100 and Pt1000 sensors is regional or international standards.

The old US standard specifies the temperature coefficient of platinum as 0.00392 Ω/Ω/°C (ohms per ohm per degree Celsius). In the newer European DIN/IEC 60751 มาตรฐาน, also used in North America, the value is 0.00385 Ω/Ω/°C. This difference is negligible at lower temperatures, but becomes noticeable at boiling point (100องศาเซลเซียส), where the old standard reads 139.2Ω while the new standard reads 138.5Ω.