Module Temperature Sensor-PT1000 with Modbus Output – 3S-MT-PT1000-MB

What is Module Temperature Sensor?

In solar power plants, module temperature has a big impact on overall field performance. It measures the backside temperature of solar panels in degrees Celsius (°C) using a PT1000 probe.

Since photovoltaic panels produce heat in addition to energy when exposed to sunlight, this measurement is crucial. This indicates that while some of the radiation is transformed into electrical energy, the remainder is emitted as heat, raising the PV cells’ temperature. The electrical efficiency of the module drops when cell temperature rises because the short-circuit current rises while the open-circuit voltage falls. As a result, keeping an eye on panel temperature is essential for tracking and controlling these efficiency losses.

What is the working principle of Module Temperature?

Module temperature sensors are professional and intelligent measuring sensors with a digital interface for environmental and industrial applications such as PV plants. The unit is a temperature measuring transmitter with RS485 sensor output, specifically designed for monitoring PV module back-side temperature. The measured value transmit to monitoring instruments with MODBUS RTU protocol. In order to communicate via Modbus RTU Protocol, a transducer is used to convert PT000 to Modbus RTU. This Module Temperature Sensor Model is compatible with all dataloggers and PLCs with RS485 input port.

Technical Specifications                

How should Module Temperature be installed?

IEC 61724-1:2021 stated that “the module temperature sensor shall be placed at the center of a cell near the midpoint of the module, avoiding cell boundaries.”

This implies that the Module Temperature Sensor needs to be positioned precisely in the middle of the PV module’s back. In order to avoid crossing cell boundaries, the sensor should be placed on the center of the cell closest to this middle point. To ensure precise measurement and a secure connection, the installation area must also be totally dry and free of impurities. It is noted that during the winter, dew residues on the PV modules could make it difficult for the Module Temperature Sensor to attach to them.

What are the advantages of Module Temperature?

In photovoltaic (PV) systems, module temperature sensors are essential because they guarantee optimal efficiency, guard against overheating, and allow for weather adaption. Here is a summary of their significance:

PR Calculation: To determine the Performance Ratio (PR) correctly, the module temperature must be measured. Since temperature directly affects electrical output and precise temperature data is required for precise PR calculations, a module temperature sensor is required.

Overheating Protection: PV panels may sustain long-term damage from excessive heat, which also lowers efficiency. Sensors give control systems real-time temperature information, which allows them to modify panel tilt or initiate cooling techniques to prevent overheating. This lowers maintenance costs, increases sustainability, and prolongs service life in addition to protecting the system.

Weather Adaptability: Climate fluctuation further influences the constantly shifting weather conditions in which PV modules function. The system may react dynamically thanks to temperature sensors, maximizing energy yield by maximizing performance in a variety of seasons and environmental situations.

Why Seven Sensor Solutions?

SEVEN products are built with reliable, high-quality components to deliver precise meteorological data for both environmental and industrial applications. A key advantage of the module temperature sensor lies in its design, which closely replicates the structure of a PV module’s backside. This ensures that the sensor and the PV module exhibit similar heat transfer behavior—an essential requirement for accurate measurement.

The sensor is specifically engineered to meet the requirements of photovoltaic plant monitoring systems, in compliance with IEC 60751:2022 and IEC 61724-1:2021 Annex B. For example, IEC 61724-1:2021, Section 9.1 specifies that for bifacial modules, rear-side temperature sensors and wiring must not obscure more than 10% of any cell area, and cabling should be routed between cells whenever possible. In addition, temperature sensors must provide a measurement resolution of ≤ 0.1 °C and an uncertainty of ±1 °C or better.

The SEVEN 3S-MT module temperature sensor fully satisfies these requirements. Our module temperature sensor delivers a resolution of ≤ 0.1 °C with an uncertainty of ±1 °C, fully aligning with the IEC standards.

Frequently Asked Questions (FAQ)

1- What is the Class?
All 3S-MT-PT1000-MB sensors are Class A according to IEC 60751:2022 and IEC 61724-1:2021.

2- What is the warranty?
All 3S-MT-PT1000-MB sensors come with a 2-year warranty.

3- What is the price of module temperature sensor?

Between 150 and 180 EUR.

4- What are the delivery times?

Small Orders: approx. 1-2 weeks

Bulk orders: approx. 6-8 weeks

5- Does the sensor include a cable?
Each unit comes with a 50 cm 2x2x0,22 mm², 24 AWG, LI2YC11Y-TP PUR Cable and 2,5 m 3x2x0,22 mm², 24 AWG, LI2YC11Y-TP PUR Cable (UV and Weather Resistant). Other lengths are available on request.

6- How do I set up the sensor?

Follow our user manual which include step-by-step instructions. The user manual link is https://www.sevensensor.com/files/d/en/Module_Temperature_Sensor_User_Manual.pdf