[Solved] NTC Temperature Sensor

Forum 2005-2010 (read only) Hardware Interfacing
1

Hi Everybody,

I'm kinda new with electronics, but i'm a good self learner. I'm gonna buy an arduino and to buy some extra components so i can make stuff.

One sensor i want to buy is a NTC Temperature Sensor, but I have no clue which resistor to use it with. I found the following schematic:

They use a 1k resistor, but how can you calculate which resistor is needed?

From the specs of the sensor i can read:
Groundresistance : 2.252 Kilo Ohm
B value : 3976 K

So my questions are:

What do those values mean?
Is this sensor any good to use with Arduino?
Which resistor is needed and how is that calculated?

Thank you for your help, I apoligize for my bad English (i'm dutch).

Regards,

Hiej

2

This sensor is simply a temperature dependent resistor (thermistor), so what you have here is a voltage divider.
The 1K resistor is used so that when the thermistor changes the voltage will change. The value is not critical and should be set to roughly the same as the thermistor value at your mid temperature range.

The B constant is a measure of how much the resistance changes with change in temperature and is a characteristic of the individual thermistor type.

3

Thank you for your reply Grumpy_Mike, I understand it now.

Regards,

Hiej