9211 gives very high temperature without any connection

[Ashraf Amin]

Hi All,

I have NI 9211 module and it was working fine at room temperature; once I finished my setup and started to  use it at higher temperature around 150 C; the labview gave a signal off 1400 C

even without having the thermocouple connected; the signal still there

you help me

Thanks 

[AdnanZ]

Have you read the spec of the 9211? It says that it has -40 to 70 °C operating range and can take a range of ±80 mV analog inputs.

[JamesBeams]

This is normal operation.  The 9211 is designed to produce a full scale high output of the thermocouple channel when no input is connected (open thermocouple).  When this is converted to temperature it will output an out of the ordinary high value.  You can use this as an indication that the measurement is not valid because the sensor is not properly connected.