How I can test and implement PT100 in circuit.....?????

Hi Guys I bought a PT100 (RTD) Thermo sensor.It has 3 wires Red,Black & White.


The first probelm which I'm facing is to how i can test this PT100 in a bridge ciucuit.....???? Suggest me the resistance value which i use in the bridge along with pt100 and how i can connect 3 wire pt100 in a bridge circuit...... please help me and give our answer through circuit diagram and label the 3 wire of pt100 in your circuit so that i can understand better.

I'm not using any amplifier with the bridge. May use it or not ??? If YES then how.....I have 741 op-amp to work with..

What I need is I want to measure the temperature from 0'C to 500'C.

I need to scale this to 0-5V range so I can interface this with 8bit ADC and atmel 80S51 microcontroller and send these digital data to PC through serial port.

Waiting for your reply...!

Start out by reading this and this.

usman_ucp said:

I'm not using any amplifier with the bridge. May use it or not ??? If YES then how.....I have 741 op-amp to work with..

What I need is I want to measure the temperature from 0'C to 500'C.

I need to scale this to 0-5V range so I can interface this with 8bit ADC and atmel 80S51 microcontroller and send these digital data to PC through serial port.

Waiting for your reply...!

Click to expand...

hi,
If you need to scale 0V thru 5V I would advise against using the very old , poor specification 741.
Ideally you require a rail to rail OPA, eg: MCP6002 or equivalent

ericgibbs said:

hi,
If you need to scale 0V thru 5V I would advise against using the very old , poor specification 741.
Ideally you require a rail to rail OPA, eg: MCP6002 or equivalent

Click to expand...

Thanx for reply

ericgibbs I'm working with 8051 atmel miccontroller.

can u provide me the diagram for the connection of pt-100 in a bridge using mcp6002 opa.....Infact the main problem i'm facing is to how i can connect the three wire of pt100 (red , black, and white).

Make sure your PT100 is rated for the higher temps. Make sure you have enough resolution in your converter. You will have to linearize the output. See This: https://www.electro-tech-online.com/custompdfs/2011/06/2-203-204-Wire20RTD20Measurement.pdf

This https://www.omega.com/pptst/PT-104A.html is not what you need, but it linearizes to 800 deg C.

Here is a transmitter for -200 to 500 C: **broken link removed** Yep, you need a power supply. That's the way industry does it.

As you can see **broken link removed** there are problems going to higher temperatures.

Last, but not least, probably something you can use: https://www.electro-tech-online.com/custompdfs/2011/06/AN709_0.pdf

usman_ucp said:

....Infact the main problem i'm facing is to how i can connect the three wire of pt100 (red , black, and white).

Click to expand...

Here's an article that covers using a three terminal pt100 in a bridge circuit.

usman_ucp said:

Thanx for reply

ericgibbs I'm working with 8051 atmel miccontroller.

can u provide me the diagram for the connection of pt-100 in a bridge using mcp6002 opa.....Infact the main problem i'm facing is to how i can connect the three wire of pt100 (red , black, and white).

Click to expand...

hi,
The information that Kiss and Carl have posted should help with the connections.
The important point that was queried, is the PT100 that you have bought OK for 500C operation.??? Can you post the type number.?

I do have some circuit diagrams for the PT100 sensor.