Endress+Hauser iTEMP TMT85, Operating Instructions Manual

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iTEMP TMT85
Operation via FOUNDATION Fieldbus TM
Hauser 79
A0042927
 21 Linear scaling of temperature-linear curve
Linearization of platinum resistance thermometers using Callendar Van Dusen coefficients:
The coefficients R0, A, B, C can be specified in the CVD_COEFF_R0, CVD_COEFF_A,
CVD_COEFF__B, CVD_COEFF_C parameters. To activate this linearization, select the "RTD
Callendar Van Dusen" setting in the SENSOR_TYPE parameter. In addition, the upper and
lower calculation limits must be entered in the CVD_COEFF_MIN and CVD_COEFF_MAX
parameters.
The Callendar Van Dusen coefficients can also be entered via the "Callendar Van
Dusen" wizard.
Linearization of copper/nickel resistance thermometers (RTD):
The coefficients R0, A, B, C can be specified in the POLY_COEFF_R0, POLY_COEFF_A,
POLY_COEFF_B, POLY_COEFF_C parameters. To activate this linearization, select the
"RTD nickel polynomial" or "RTD copper polynomial" setting in the SENSOR_TYPE
parameter, depending on the sensor element used. In addition, the upper and lower
calculation limits must be entered in the POLY_COEFF_MIN and POLY_COEFF_ MAX
parameters.
The coefficients for the nickel and copper polynomials can be entered with the aid of a
wizard in the Sensor 1 and 2 Transducer Blocks.
Each of the values can be passed onto an AI function block or shown on the display. The AI
Block and the Display Block provide additional ways for displaying and scaling measured
values.
Block configuration error:
The device may display the diagnostic event "437-configuration" due to an incorrect
setting. This means that the current configuration of the transmitter is not valid. The
BLOCK_ERR_DESC1 parameter in the Transducer Blocks displays the reason for this
configuration error.
Display Description
Sensor 1 is 4 wire RTD and sensor 2 is
RTD If sensor 1 is configured as a 4 wire RTD, an RTD cannot be selected
at sensor 2.
Sensor type 1 and sensor unit 1 do not
match The sensor type at channel 1 and the selected sensor unit do not
match.
Sensor type 2 and sensor unit 2 do not
match The sensor type at channel 2 and the selected sensor unit do not
match.