What is a Pt100, and do I need one for my temperature application?

What is a Pt100 sensor?

A Pt100 sensor is a type of platinum or platinum-coated resistance temperature detector (RTD) accessory that measures temperatures in an external application. RTD sensors change resistance when temperatures change, allowing processors to maintain target temperatures accurately. Pt100 sensors measure resistance in 100 Ω (ohms) at 0°C and are one of the most common accessories in laboratory and industrial processing, heating, and cooling. 

Pt100 Sensor Benefits

A Pt100 sensor allows you to get accurate, safe, and repeatable results by monitoring temperature changes at the application site, such as inside a reactor, bioreactor, or fermenter. Proper temperature control is essential for many processes and reactions as it directly affects safety, quality, and yields. 

Pt100 sensor benefits include:

• Accurate temperature readings across a wide range of temperatures
• The ability to withstand vibration
• Easy installation
• Protection for process heating and cooling applications, leading to a great return on investment
• Greater accuracy and stability compared to a thermocouple, which has measurements that can drift over time. 

Do I Need a Pt100 Sensor for my temperature application?

You’ll want to use a Pt100 sensor for any process where temperature control is critical for your results. Pt100 sensors provide external temperature control and monitoring for chemical and biochemical processes that rely on precise heating and cooling. The Pt100 sensor attaches to the temperature control unit on one end. The end with the sensor can then be placed directly in the sample vessel to ensure safety, compliance, and reproducibility. Many industries and applications, including pharma, biotechnology, aerospace, automotive, defense, food production, etc, use Pt100 sensors 

What’s the difference between a Pt100 sensor and a thermocouple? 

A thermocouple is a different type of temperature sensor. Unlike the RTD/ Pt100, a thermocouple doesn’t measure resistance; instead, it contains two dissimilar metals that vary voltage based on the temperature. A thermocouple responds quicker than an RTD sensor but lacks the level of accuracy and reproducibility you receive with a Pt100 sensor. The outside diameter or “OD” on thermocouples is generally smaller than that of an RTD, making thermocouples a good choice for applications with smaller openings. JULABO USA sells thermocouple converter kits with mini-connectors allowing you to plug the thermocouple converter into the Pt100 on the back of a JULABO to provide thermocouple capabilities.

Find a Pt100 Sensor for Your Application

JULABO offers a variety of Pt100 sensors with ¼” OD and varying lengths (8″ to 48″) and in-line sensors for applications that cannot accommodate an internal sensor. Choose from 316SS (stainless steel) sensors or PTFE (Teflon) coated sensors. While the 316SS sensors resist corrosion, the PTFE sensors offer even more protection for applications that could corrode 316SS. Your account manager can also source custom sensors of different dimensions and capabilities, including alternate materials such as Hastelloy.

How Do I Connect a Pt100 Sensor?

Most of JULABO USA’s external temperature control units come with a Pt100 connection, which allows you to plug in a Pt100 sensor with a Lemosa 4-pin directly into your JULABO unit. The PRESTO process temperature control systems, MAGIO, and DYNEO DD circulators come with a Pt100 port. To learn more about connecting a Pt100 sensor to your JULABO and putting the unit into the external mode, check out our YouTube Pt100 playlist. 

Conclusion & Next Steps

If you are heating or cooling an external application, look for a temperature control system, chiller, or circulator that allows you to connect a Pt100 sensor. The Pt100 sensor will protect your application results and provide reliable temperature measurements. By monitoring your temperatures directly at the application site, you’ll increase yields, and get reliable, reproducible results. You can shop for various Pt100 sensors on the JULABO website. If you need assistance or have any questions about your external temperature control application, contact sales@julabo.us.