This document is relevant to: all Duet boards
Firmware versions: all firmware versions
The Duet series supports 4 types of temperature sensor: thermistor, PT1000, thermocouple, and PT100.
A number of Digital Humidity and Temperature (DHT) sensors are also supported:
For details of the DHT sensors, see Connecting Digital Humidity and Temperature sensors
Here are the pros and cons of each:
| Property | Thermistor | Thermocouple | PT100 | PT1000 | DHT11 | DHT21/22 | BME280 |
|---|---|---|---|---|---|---|---|
| Cost | Low | Medium | Higher | Higher | Low | Low | Low |
| Precision | Low | Medium | High | Medium | Medium | Medium | Medium |
| Needs adapter board? | No | Yes | Yes | No | No | No | No |
| Susceptible to interference? | No | Very | Somewhat | No | No | No | No |
| Temperature limit | Typically 280-300C | Up to 1100C depending on type | Up to 500C depending on type | Up to 500C depending on type | 0-50C | -40 to 80C | -40 to 85C |
| Special considerations | Because thermistors are not very accurate, if you replace the thermistor or the electronics then the readings may change by several degC. So you may have to re-learn what temperature indications give you good prints. | To get accurate cold junction compensation, you need to run the twisted pair thermocouple leads all the way from the hot end to the adapter board. So you can't easily include the thermistor connections in a connector for a demountable hot end. | For best accuracy, use a 4-wire connection | Lower resolution than other sensors. | Suitable only for chambers or other lower temperature applications. Measures humidity as well as temperture. BME280 also measures pressure. DHT11 not supported from firmware v3.4 and later. | ||