NTC thermistors and thermistors

What is a thermistor

A thermistor is a device that is used to measure and control the temperature in 3D printers and other CNC machines. In fact, the thermistor (thermistor) plays a very important role, because maintaining a constant temperature and its control on the hot-end and heating table is the key to high-quality and successful printing. Several types of sensors such as thermocouples and resistive sensors (RTD) are used for control. But the most widespread and in demand are thermosensitive resistors - NTC thermistors.

The advantages of thermistors:

• All models of thermistors are easy to install and maintain;
• Their cost is an order of magnitude lower than other temperature-sensitive sensors;
• NTC thermistors are easy to integrate into any controller board

The thermistor design

. The most common model of thermistor is a resistor, which is located in a hermetically sealed glass or metal bulb. Such models of thermistors are used in almost all modern 3D printers. In our online store you can buy thermistors represented by the following models:

• Thermistor SM2P HT-NTC 100K 3950, 20mm;
• ATC Semitec 104NT-4-R025H42G thermistor;
• Thermistor SM2P HT-NTC 100K 3950, 15mm;
• Trianglelab thermistor 104GT-4-R025H42G;
• Thermistor NTC100K with JST/SM connection;
• NTC100K thermistor;
• NTC100K thermistor with XH-2.54 (high temperature) connection;
• NTC100K thermistor with XH-2.54 connection;
• NTC100K thermistor with 2P DuPont connection;

Thermistor characteristics:

• Resistor resistance: 100 kOhm;
• Operating temperature range: -40 °C to +350 °C;
• Accuracy class: 1 (± 1%);
• Cable length: 1m, 2m;

The working principle of thermistor

. The principle of operation of the thermistor is quite simple. Using a pair of wires, the thermistor is connected to the controller. As the working bodies heat up, the resistance of the resistor in the thermistor changes, and these changes are transmitted to the controller, where a special microprogram compares the received temperature data with the set parameters, and then adjusts the temperature in case of its deviation fr om the set parameters in one direction or another.

NTC Thermistor on a 3D printer

Thermistors can be found in several places on an FDM printer. On the hot end, wh ere the printer nozzle screws into a heating block whose job is to heat and melt the filament. There are two pairs of wires connected to this block. The first feeds the ceramic element that heats the block, and the second is connected to a thermistor built into the space inside the block so that its internal temperature can be measured accurately.

The location of the thermistor on the workbench is less obvious. It is usually located below the surface of the printing plate. In printers with a heated chamber you can find a thermistor that measures the internal temperature.

The thermistor is a very important sensor in a 3D printer, but for some reason it is very often overlooked. After all, with a faulty thermistor, print quality will drop dramatically, especially if you are working with engineering plastics. It is quite easy to replace the thermistor, and our staff will help you to choose and buy the necessary model of thermistor.