Temperature Probe LM235Z: Precision in Temperature Measurement

Temperature monitoring is essential in HVAC systems, building automation and industrial applications where efficiency, safety and product quality depend on reliable data. Among the different sensor technologies, the Temperature Probe LM235Z offers an attractive combination of precision, fast response and cost‑effectiveness for low‑ to medium‑temperature applications. This article explains what the LM235Z temperature probe is, how it works, where it is typically used and why Andivi LM235Z cable probes are a smart choice for modern automation projects.

What is an LM235Z Temperature Probe?

Cable Surface Temperature Probes LM235Z

Cable Surface Temperature Probes LM235Z

The LM235Z is a precision semiconductor temperature sensor that converts temperature directly into a voltage signal. Electrically, it behaves similarly to a Zener reference; its output voltage changes linearly with temperature, which makes temperature calculation very straightforward. In practice, this means that each degree of temperature change results in a nearly constant change in voltage at the sensor output.

In typical applications, LM235Z probes cover a measuring range of approximately -40 °C to +100 °C (up to about +125 °C, depending on design and housing). Within this range, they provide a good level of accuracy for comfort and many industrial processes, usually around ±1 °C under standard conditions. Compared to platinum RTD sensors such as PT1000, the LM235Z uses a silicon integrated circuit instead of a resistive metal element, which allows compact construction, lower cost and very fast reaction to temperature changes.

How Does the LM235Z Work?

Temperature Probes Threaded LM235Z

The LM235Z is designed as an integrated circuit that outputs a voltage proportional to the absolute temperature. When supplied with a suitable constant current, the sensor’s output voltage increases linearly with rising temperature. For system integrators, this is particularly convenient because the controller only needs an analog voltage input and a simple scaling formula to convert the measured voltage into degrees Celsius.

In Andivi cable probes, the LM235Z chip is typically encapsulated in a robust housing – for example a TO‑92 package embedded in a stainless‑steel sleeve or plastic probe – and connected to a cable. The low thermal mass of the sensing element and the compact probe design ensure short response times, which is especially useful in applications where the temperature can change quickly and needs to be tracked in near real time.

Typical Applications and Industries

Because of its balance between price, precision and speed, the Temperature Probe LM235Z is widely used in low‑ to medium‑temperature applications. Typical sectors include:

• HVAC Systems

  • Room, duct and pipe temperature monitoring in heating, cooling and ventilation systems.

    

    Oscillating Temperature Probes LM235Z

  • Comfort control in residential, commercial and public buildings, where accuracy of around ±1 °C is fully sufficient.

  • Energy‑efficient regulation of boilers, chillers, heat pumps and air handling units.

• Building Automation

  • Measuring indoor temperatures in offices, corridors, technical rooms and other building zones.

  • Integration into building management systems as cable, duct or wall sensors.

  • Multipoint temperature monitoring in larger buildings where many cost‑effective sensing points are required.

• Industrial and Process Applications

  • Monitoring of enclosures, switch cabinets and machinery surfaces within moderate temperature ranges.

  • Use in OEM equipment and control boards where a compact, easily calibrated temperature sensor is needed.

  • Temperature supervision in smaller process lines or auxiliary circuits that do not require extreme accuracy or very high temperatures.

• Laboratory, Test and OEM Electronics

  • Use in test benches and laboratory equipment as a simple voltage‑based temperature reference.

  • Protection and monitoring in chargers, power supplies and other electronic devices.

Cable Materials and Temperature Ranges

As with other Andivi cable temperature probes, LM235Z sensing elements can be combined with different cable insulations to suit various operating environments. While the LM235Z defines the measuring range of the sensor tip, the cable material defines the allowable cable temperature and environmental resistance.

Image	Cable material	Temp.	Thermocouples available
	PVC Cable	up to 105°C	LM235Z Also available: PT100 1/3DIN, PT 1000, PT1000 1/3DIN, NI1000, NI1000TK5000, NTC 5k / 10k / 20k / Precon / KTY81-210, NTC 1,8 kOhm, DS18B20
	Silicone cable	up to180°C	LM235Z Also available: PT100 1/3DIN, PT 1000, PT1000 1/3DIN, NI1000, NI1000TK5000, NTC 5k / 10k / 20k / Precon / KTY81-210, NTC 1,8 kOhm, DS18B20
	High-temperature silicone cable	up to 260°C	LM235Z Also available: PT100 1/3DIN, PT 1000, PT1000 1/3DIN, NI1000, NI1000TK5000, NTC 5k / 10k / 20k / Precon / KTY81-210, NTC 1,8 kOhm, DS18B20
	Glass wool cable	up to 400°C	LM235Z Also available: PT100 1/3DIN, PT 1000, PT1000 1/3DIN, NI1000, NI1000TK5000, NTC 5k / 10k / 20k / Precon / KTY81-210, NTC 1,8 kOhm, DS18B20

This flexibility in cable types allows planners and installers to select a mechanical and thermal configuration that matches both the sensor’s operation and the route of the installation.

Technical Specifications of LM235Z Temperature Probes

Typical technical characteristics of LM235Z‑based temperature probes include:

These parameters can be adapted within Andivi’s product portfolio, for example, by selecting different cable lengths, cable materials or probe geometries.

Where Does LM235Z Fit Among Passive, Active and Modbus Sensors?

Temperature sensors used in building and industrial automation can be grouped into three main families: passive sensors, active sensors and Modbus (digital) sensors.

• Passive sensors (PT100, PT1000, NTC, Ni1000, LM235Z, DS18B20)
  Passive sensors do not generate a powered output on their own – they change resistance, voltage or a digital code that the controller has to read directly. PT100/PT1000 and NTC/Ni1000 elements are read as resistance, DS18B20 provides a digital 1‑Wire interface, while LM235Z delivers a linear voltage proportional to temperature. They are ideal where the controller already has suitable inputs and cable lengths are moderate.

• Active sensors (4–20 mA, 0–10 V)
  Active sensors integrate the measuring element and electronics in one housing and output a standardized current or voltage signal. This makes them perfect for long cable runs, industrial environments with strong electromagnetic interference and cases where a universal PLC or building controller only offers analog inputs.

• Modbus sensors
  Modbus temperature sensors combine the measuring element, electronics and a digital RS485 interface in one device. They are used when many measuring points have to be networked over one bus cable, when additional parameters (humidity, CO₂, etc.) are needed at the same location or when diagnostics and configuration via software are required.

LM235Z clearly belongs to the family of passive temperature sensors but is special because it outputs a linear voltage instead of a resistance change, which makes integration into simple analog voltage inputs particularly straightforward.

Why Choose Andivi LM235Z Temperature Probes?

Andivi develops LM235Z temperature probes specifically for professional use in HVAC, building automation and industrial applications. Several advantages speak in favour of this solution:

• Certified quality and sustainability
  Andivi operates under ISO 9001 (Quality Management) and ISO 14001 (Environmental Management) standards, which ensures consistent product quality and environmentally responsible manufacturing processes.

• Excellent price‑performance ratio
  LM235Z probes offer a very attractive balance between cost and performance, especially in projects with many measuring points where budget and reliability are equally important.

• Versatile application options
  LM235Z sensing elements can be integrated in cable probes, duct sensors, surface probes and special housings, making them suitable for a wide range of installation situations in buildings and industry.

• Customizable configurations
  Customers can choose different cable lengths, cable materials, probe dimensions and accessories such as immersion sleeves or mounting brackets, ensuring that each sensor matches the project’s technical and mechanical requirements.

• European manufacturing
  Andivi sensors are manufactured in the EU under strict quality control, resulting in robust, durable probes designed for real‑world operating conditions.

For HVAC and building automation projects that require reliable temperature monitoring in moderate temperature ranges, LM235Z cable probes provide an excellent combination of precision, speed, simplicity and cost‑effectiveness.