Aurimas Posted August 16, 2017 Report Share Posted August 16, 2017 Hello, I have a problem with messuring temperatures. The setup goes as follows - V700 - EX-A2X - IO-PT4K-PT1000 sensor. IO-PT4K type is PT100/1000(alpha=0.392) mode is Celsius . I get values like 220, 200 that seems to be like temperature 22 multiplied by 10. Why are these values so high or it is just coinsidense. Also the keep changing like from 170 to 220 in seconds so I can't build control based on temperature messuring. Any thoughts? Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted August 16, 2017 MVP 2023 Report Share Posted August 16, 2017 Thermocouple inputs normally have an implied decimal point to give you a reading in tenths of a degree. Either display the value using the implied decimal, or divide by 10 to get an integer value. There are filters available to help stabilize the temperature reading, if needed. Link to comment Share on other sites More sharing options...
Aurimas Posted August 16, 2017 Author Report Share Posted August 16, 2017 I tried dividing by ten to display it. Where could I find these filters to stabilise the temperature reading? Link to comment Share on other sites More sharing options...
MVP 2023 Flex727 Posted August 16, 2017 MVP 2023 Report Share Posted August 16, 2017 There is a filter built-in to the Hardware Configuration for the sensor input. In addition, there are filter Function Block options available under the Function Block (FB) drop down menu when in ladder view. Link to comment Share on other sites More sharing options...
MVP 2023 Ausman Posted August 16, 2017 MVP 2023 Report Share Posted August 16, 2017 But if you are having such large variations on a PT100/1000 I suspect there is something wrong in the wiring. Long run? Screened? Correctly terminated including the screen? A myriad of other things to look at. The reading should innately be very stable. cheers, Aus Link to comment Share on other sites More sharing options...
hotwires Posted August 26, 2017 Report Share Posted August 26, 2017 On August 16, 2017 at 5:41 PM, Ausman said: But if you are having such large variations on a PT100/1000 I suspect there is something wrong in the wiring. Long run? Screened? Correctly terminated including the screen? A myriad of other things to look at. The reading should innately be very stable. cheers, Aus Screened must be the Austrialian term for shielded. Screen makes me think of the second grid in a pentode electron tube. The British call electron (vacuum) tubes "vavles". Which makes sense, they are valves for electrons. Link to comment Share on other sites More sharing options...
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