Measurement Computing UL for NI LabVIEW - Manual (Page 34)

Universal Library Virtual Instruments (VIs) Analog Input VIs
TIn.VI
Changed R3.3 ID
Reads a temperature input channel, linearizes it according to the configured temperature sensor type, and
returns the temperature in degrees. The CJC channel, gain, and sensor type are read from the configuration
file. They should be set by running the InstaCal configuration program.
Summary:
Inputs: BoardNum [U32] - The board number assigned when installed with InstaCal. Can
be 0 to 100..
Chan [U32] - Channel to read
Scale [U32] - The temperature scale used to calculate the temperature in degrees.
Options [TF] - Bit that controls data smoothing (averaging) option (True).
" FILTER " (True) is default.
Outputs: Temperature [SGL] - Temperature returned here.
ErrCode [I32] - Error code. See ErrMsg.VI
Arguments:
BoardNum The board number associated with a board when it was installed with InstaCal.
Chan Input channel to read. For EXP boards, the channel number is calculated using the
following formula:
A/DChan = A/D channel the multiplexer ("mux") is connected to
MuxChan = Mux board input channel number
Chan = (ADChan+1) * 16 + MuxChan
For example, if you had an EXP16 connected to a PCI-DAS08 via the PCI-DAS08
channel 0 (remember, DAS08 channels are numbered 0, 1, 2, 3, 4, 5, 6, and 7), and
if you had a thermocouple connected to channel 5 of the EXP16, the value for
Chan would be (0 + 1) x 16 + 5 = 21.
Scale Specifies the temperature scale that the input will be converted to. Choices are
CELSIUS , FAHRENHEIT and KELVIN .
Options FILTER : The TIn.VI applies a smoothing function to thermocouple readings very
much like the electrical smoothing inherent in all thermocouple instruments. When
selected, 10 samples are read from the specified channel and averaged. The
average is the reading returned. This is the default.
NOFILTER : If you use the NOFILTER option (False), the thermocouple readings will
not be smoothed and you will see a scattering of readings around a mean.
Temperature The temperature in degrees is returned here. Resolution is hardware dependent.
ErrCode Error code returned from the Universal Library. Zero if no error occurred. Use the
ErrMsg VI to convert ErrCod e into a readable string.
A/D Range – IMPORTANT
If an EXP board is connected to an A/D that does not have programmable gain then the A/D board input range
is read from the configuration file (CB.CFG). In most cases, hardware-selectable ranges should be set for
±5 V for thermocouples and 0 to 10 V for RTDs. If the board does have programmable gains, the
TIn.VI will
set the appropriate A/D range. Refer to the board-specific information for details.
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