Siemens SITRANS T3K PA, Instruction Manual

Page: 91 / 130

Instruction Manual 7NG3213
SITRANS T3K PA
C79000-B7174-C55-04
91
3.4 Line adjustment
A line adjustment is necessary at the following measurements:
– Two-wire resistance thermometer or resistance based sensor
– Differentiating or averaging connection for resistance thermometer or resistance
based sensor
– Thermocouple with external reference point with Pt100 in two-wire circuit
The adjustment is made by numeric setting of the measured line resistance (sum,
feed and return line).
3.5 Line resistance
Depending on the circuit you can measure the line resistances on channel 1 and
channel 2 or the line resistance to the external RTD (as a reference point to a
thermocouple). To do this, you have to short-circuit the appropriate channels and
activate the parameter for line resistance measuring.
The measured resistance values are obtained in the parameters for the line
compensation. In addition you receive the result whether the measurement has
been made correctly and the measured resistances have been entered.
3.6 Mains frequency filter
With this filter you can set an interference suppression of the mains frequencies of
50 or 60 Hz. 10 Hz can also be set as a special function.
3.7 Scaling factor
This factor is used for characteristic adaptation, e.g. in the serial and parallel
circuiting of sensors or resistance based sensors. Values of 0.1 to 10.0 can be set
for the scaling factor.
3.8 Reference selection for measuring by means of a
thermocouple
Here you can select the connection type of the RTD as a reference point for a
measurement using a thermocouple: use the built-in RTD or an external one
which is necessary when the measuring point is remote from the
SITRANS T3K PA.