I/ PT400

[pero3694]

Hi,

I’m using i/o pt400 expansion module and on it pt100 with 3 wire.

i can’t get goof linearization of it?

pt100 is for tempeture -200 tll 600 *C and the module is from -50 till 460...

any help?

[Gabriel Franco]

Use LINEARIZATION FB.  Keep in mind module resolution is 0.1°C, that´s the reason X1 and X2 values are -2000 ... 6000 in the image

 

[Isakovic]

You don't need linearization for PT100. Module itself does that and gives you result x10 (value 123 would be 12.3 degrees). You just choose °C or °F in hardware configuration.

[pero3694]

6 hours ago, Gabriel Franco said:

Use LINEARIZATION FB.  Keep in mind module resolution is 0.1°C, that´s the reason X1 and X2 values are -2000 ... 6000 in the image

 

I’m using it. X1 i putted -2000 and x2 is 6000.y1 is 0 and y2 is 4095 because i/o module is 12 bits. Is it possible to put -200 and 600 because bodule can take od from -50 to 460?

[pero3694]

1 hour ago, Isakovic said:

You don't need linearization for PT100. Module itself does that and gives you result x10 (value 123 would be 12.3 degrees). You just choose °C or °F in hardware configuration.

I tried that too now, and i got diferrence 2 *C ( other mesuarment is with Ic camera and with fluke 289 multimeter)

[Isakovic]

Pt100 are resistive probes, error could be in cable resistance (if cross section of those 3 wires is not the same), in some bad contact or EM interference. If those 2 °C is static error you could add offset in the program to take it into account or try filtering it.

[Joe Tauser]

An IR camera is no where near as accurate as an RTD probe due to variances in emissivity of the surface being looked at and the setting in the IR sensor.  In fact, an RTD or thermocouple is to calibrate all IR devices.

I'm not sure how you're using the Fluke 289, as it does not have 4-wire lead compensating resistance.

I would believe what the RTD module is telling you over the other two instruments.

Joe T.