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Verfügbare Sprachen
Verfügbare Sprachen
NOTE!
The analog input can only be used as an alternative to digital input 2 with signal type 0(2) up to 10 V.
Resistance Ra or Ro, Rs or Rx, Re
The overall resistance Ra + Rs + Re (or Ro + Rx) must not exceed 4000 Ω.
Resistance transmitter
E
Re
Rs
S
A
Ra
Filter time constant
The filter time constant is used to adjust the digital input filter (2nd order filter). If the input signal changes suddenly,
approx. 26 % of the change is recorded following a period that corresponds to the filter time constant (2 × filter time
constants: approx. 59 %; 5 × filter time constants: approx. 96 %). A large filter time constant means: high attenuation of
interference signals, slow reaction to the actual value display, low limit frequency (low-pass filter).
9.5.1 Fine adjustment
You can use this function to correct the measured values of the analog input. In contrast to measured value offsetting,
which is used to specify a constant correction value for the entire characteristic line, fine adjustment can also be used
to change the gradient of the characteristic line.
Example
The temperature inside a furnace is measured with an RTD temperature probe connected to the device. The measured
value displayed by the device deviates from the actual temperature as a result of the sen sor temperature drifting. The
amount of deviation is different at the lower measuring point (start value) and at the upper measuring point (end va-
lue), meaning a measured value offset correction is not suit able. The actual temperature (reference value) is determined
using a reference measuring device.
Actual start value: 15 °C (measured value)
Target start value: 20 °C (reference value)
Actual end value: 70 °C (measured value)
Target end value: 80 °C (reference value)
Product:
Temperature controller XT-T1
Resistance/potentiometer in two-
wire circuit
Rx
Ro
Revision 2.0 – Issue September 2018
Resistance/potentiometer in three-
wire circuit
Rx
Ro
E
117 /166
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