PT100 Question

[place1234]

Having one Reliance motor, in the RTD specification they write: "PlATINUM,0.00392 TCR".
I'am try using AllenBradley RTD input module , but as of the "input type selection", one is the 100PT(385), other one is the 100PT(3916). Which one shall select then to make the bit seeing in the channel configuration word for the SLC Slack?

 

[itsmoked]

3916 is the closest and will probably work just fine.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[place1234]

Could you tell me why?

 

[itsmoked]

Do you understand what the numbers are for?

They represent the alpha of the resistance - temperature equation for RTDs. There have been two standards for a long time. The American 0.0392 one and the European 0.0385 value. They have been slowly mixing and matching to where I would say the European one is now more common. The 3916 you are mentioning is really referring to 0.03916 which is close to 0.0392. I'm not sure if they are the same or not. I have never come across 0.03916 stated before, but someone is always coming along with 'their better way'. At any rate call it 0.0392 and then check it via calibration.

Keith Cress
Flamin Systems, Inc.-

http://www.flaminsystems.com

 

[aolalde]

See the following link, this manufacturer makes both Platinum RTD’s, 392 and 385 or TCR 0.00392 and TCR 0.00385. You could contact them for technical advise.

http://www.minco.com/uploadedFiles/...uments/RTD_&_Thermocouple_Probes/Ts103A_3.pdf