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PT-100/PT-1000 problem..
#1
I am having trouble with this device.. I have 3-wire PT100 connected to the device (bought them by mistake, but they should work the same (?) ), 2 red wires are connected together to the 1,2,3,... and the white wire is connected to the bottom connectors.. 

the problem is that it is sending, for the 8 sensors, the same value.. 83,5ºC no difference between them, and inverting the connection happens the same, sometimes sends other value but it has nothing to do with the real values.

Do i need to buy 2wires PT100? is there any configuration for PT100 different than PT1000? should I buy PT1000?

Thanks.
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#2
Just by the resistance measurement PT1000 has 10 times higher value then PT100 or other way around Smile. Where did you connect it ?
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#3
Try measuring resistance between wires using a multimeter. PT100 has 100 ohm @ 0C, PT1000 has 1000. You should use PT1000 because PT100 has very low precision.
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#4
I have connected a PT1000 to the device, and it is sending 154.88ºC, does the PT100/PT1000-KNX auto-detects if there is a PT100 or a PT1000 connected? or do I have to upload a different KNX database?.
Tested the probes and the resistance is between 107 to 120º when heated with the hands...
also, I've connected several resistors directly to the device (from 100 to 1200 ohm), and it returns values of the sort.. 86,8º, 213º, etc..
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#5
Can you show how the sensor is connected? One wire to GND another to input? Polarity does not matter. Keep in mind that GND is on the other side.
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#6
This is the connection I have.
   

also tried it with a resistor 1K, 1.2K ohm and the value returned was aprox. 200º also with 100 ohm resistors the temp values were the same as before.
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#7
Is there any technical document, explaining How to configure this module?. Is this module connected using RS485 port in LogicMachine?. Is there any profile for it?. How to configure comunications in the module, speed transmition, parity, slave address?
best regards
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#8
It is connected via KNX
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