---
title: "Temperature Sensing: RTD4 and T4"
description: "## Introduction This tutorial explains how to measure temperature using NORVI X expansion modules. It covers two temperature-sensing solutions: the NORVI X-RTD4, which supports PT100 and PT1000 RTD sensors, and the NORVI X-T4, which supports 2-wire NTC thermistors. ## Required…"
url: "https://norvi.io/docs/norvi-rtd4-t4-temperature-sensing/"
updated: "2026-09-21"
category: NORVI X / NORVI X TUTORIALS
---

# Temperature Sensing: RTD4 and T4

## Introduction

This tutorial explains how to measure temperature using NORVI X expansion modules. It covers two temperature-sensing solutions: the NORVI X-RTD4, which supports PT100 and PT1000 RTD sensors, and the NORVI X-T4, which supports 2-wire NTC thermistors.

## Required Hardware

| Device | Temperature Sensor | Sensor Type | Channels |
| --- | --- | --- | --- |
| NORVI X-RTD4 | PT100 / PT1000 | RTD | 4 |
| NORVI X-T4 | NTC Thermistor (10kΩ) | 2-wire NTC | 4 |

## Understanding the Sensors

### PT100 / PT1000

![](https://norvi.io/wp-content/uploads/2026/09/PT100-PT1000.png)

- RTD (Resistance Temperature Detector)
- Resistance changes with temperature
- PT100 = 100 Ω at 0°C
- PT1000 = 1000 Ω at 0°C
- Used with the X-RTD4

### NTC Thermistor (10kΩ)

![NTC Thermistor (10kΩ)](https://norvi.io/wp-content/uploads/2026/09/NTC-Thermistor-10kΩ_.png)

- NTC = Negative Temperature Coefficient
- Resistance decreases as temperature increases
- 2-wire sensor connection
- Used with the X-T4

## NORVI X-RTD4 – PT100 / PT1000

The NORVI X-RTD4 is a 4-channel RTD temperature input module. It reads 4 sensor inputs and is used in industrial, HVAC, and process monitoring applications.

### A. Sensor wiring

![](https://norvi.io/wp-content/uploads/2026/09/RTD.jpg)

The **NORVI X-RTD4** supports **PT100 and PT1000 RTD temperature sensors**. PT100 has a nominal resistance of **100 Ω at 0°C**, while PT1000 has **1000 Ω at 0°C**. For a **2-wire connection**, connect the two sensor wires to the corresponding RTD input terminals. The X-RTD4 provides **four channels (RTD1–RTD4)**, allowing up to four PT100 or PT1000 sensors to be connected and used for temperature measurement.

### B. Sensor configuration

![](https://norvi.io/wp-content/uploads/2026/09/pt100-and-pt1000-switch.jpg)

1. Connect the X-RTD4 to the NORVI X CPU.
2. Connect the PT100 or PT1000 sensor to the corresponding RTD input terminals.
3. Select the appropriate sensor type using the DIP switch.
   - Set the DIP switch to PT100 when using PT100 sensors.
   - Set the DIP switch to PT1000 when using PT1000 sensors.
   - PT100 and PT1000 sensors cannot be used together at the same time. All connected sensors must be the same type selected by the DIP switch.
4. Configure the input according to the selected sensor type.
5. Read the measured temperature.

## NORVI X-T4 – 2-Wire NTC Thermistor

The NORVI X-T4 is a 4-channel NTC thermistor temperature input module. It reads 4 sensor inputs and supports 2-wire NTC thermistors for cost-effective temperature sensing.

### A. Sensor wiring

![](https://norvi.io/wp-content/uploads/2026/09/t4.jpg)

For a 2-wire NTC sensor, connect the two sensor wires to the corresponding input terminals of Channel 1–4. The NTC sensor is non-polarized, so either wire can be connected to either terminal. Ensure that the sensor is connected to the correct channel and terminals.

### B. Sensor configuration

1. Connect the X-T4 expansion module to the appropriate expansion port on the NORVI X CPU.
2. Connect the NTC thermistor. Connect the 2-wire NTC thermistor to the selected input channel. Since the NTC is non-polarized, wires can be swapped within the same channel.
3. Configure the thermistor parameters such as the NTC resistance value and temperature parameters, according to the sensor and specifications.
4. Read the temperature value from the corresponding X-T4 input channel after completing the configuration.

## Software / Programming

**Set Up → Configure → Upload → Monitor → Verify**

1. Arduino IDE Setup
   Configure the board and communication port:

- **Tools → Board → ESP32 Arduino → ESP32S3 Dev Module**
- **Tools → Port → Select the corresponding COM/serial port**

Under the **Tools** menu, configure the following settings:

| Setting | Selection |
| --- | --- |
| USB CDC On Boot | Enabled |
| Flash Size | 16MB (128Mb) |
| PSRAM | QSPI PSRAM |

1. Required Libraries
    Install the [libraries](https://github.com/NORVIControllers/NORVI-X-Version-02/tree/main/libraries) required for the NORVI X CPU and temperature module.

- Wire
- SPI
- TFT_eSPI
- CST816S
- Adafruit_ADS1X15
- Free_Fonts

1. Upload the Example Code
    Connect the NORVI X CPU via USB, select the correct COM port, and upload the program.

## Testing the Temperature Sensor

### Test 1 – Room temperature

- Connect sensor
- Read temperature
- Record value

### Test 2 – Change the temperature

- Warm the sensor carefully
- Observe the temperature increase
- Compare the readings

### Test 3 – Multiple sensors

- Connect sensors to several channels
- Display each channel separately.

## Troubleshooting

| Module | Error / Symptom | Possible Cause | Solution |
| --- | --- | --- | --- |
| X-RTD4 | Reading pinned at fault/max value | Open circuit - disconnected sensor or broken lead | Check continuity with multimeter; reseat terminals; replace probe |
| Reading pinned at 0 °C / short fault | RTD+ and RTD - shorted together | Inspect for pinched/bridged leads; confirm terminals aren't touching |  |
| Reading slightly high | Lead resistance (2-wire) | Shorten cable / use 2 wire |  |
| Reading way off | PT100/PT1000 mismatch | Correct sensor type setting |  |
| Noisy reading | Near AC/relay/motor wiring | Reroute, use shielded cable |  |
| X-T4 | Extreme low reading | Open circuit | Check continuity, reseat terminals |
| Extreme high / 0 Ω | Leads shorted | Inspect wiring |  |
| Reading offset | Wrong Beta value | Use correct datasheet value |  |
| Slow drift | Self-heating / loose contact | Check excitation, tighten terminals |  |
| No response to temp change | Faulty sensor or wrong channel | Swap sensor, verify channel |  |

## Comparison: X-RTD4 vs X-T4

A final comparison would help users choose the appropriate module.

| Feature | X-RTD4 | X-T4 |
| --- | --- | --- |
| Sensor | PT100 / PT1000 | NTC Thermistor (10kΩ) |
| Sensor technology | RTD | Thermistor |
| Connection | 2-wire | 2-wire |
| Inputs | 4 | 4 |
| Typical use | Industrial temperature measurement | General temperature sensing |