Specifications

CONAX BUFFALO TECHNOLOGIES TSD 43.021
Rev. ORIG
Page 21 of 28
Please Note: The calculated values may be verified by using the device in
simulation mode (Alt+S from the main screen) and seeing that the device indeed
provides the proper temperatures (and/or output values in mA) for the resistances
found by the element’s tests, or vice versa.
6.7 POLYNOMIAL FUNCTIONS
Some sensor outputs can be characterized by a non-linear transfer function of the
form shown in Equation 1. If the transfer function can be described using such a
multi-order polynomial (max 10
th
order), then the sensor’s output may be linearized
by the transmitter using “Polynomial” mode in the “Input Sensor Selection” screen.
When selected, an input screen, like that shown in Figure 13, will popup asking for
the coefficients to Equation 1 (shown below).
Equation 1 – Polynomial Input Feature
10
10
3
3
2
210
)( tAtAtAtAAtutSensorOutp +++++= K
Figure 13 – Polynomial Input Feature
7.0 Trimming
Realizing that some sensor or system outputs may vary from their ideal output
curves, the trimming function allows the user to fine-tune the SPM calibration to
match the specific sensor or system back to ideal conditions. The trimming function
is a smart substitute for common “zero” and “span” adjustments found on
transmitters.