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Potentiometric transducer 279, Potentiometric transducer calibration 279 – West Control Solutions KS98-1 User Manual

Page 279

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Resistance thermometer Pt 100
The two ranges -200,0...+250,0 °C and -200,0...+850,0 °C are configurable ( r

type).

Connection in two or three-wire circuit is possible. Copper lead must be used for measurement. The input circuit monitoring re-
sponds at -130°C (sensor or lead break). The action is configurable for:

Upscale ( << process value)
Downscale ( >> process value)
Substitute value (the entered value is used as measured value in case of failure.

Resistance thermometer in 2-wire connection:

For lead resistance adjustment, disconnect the input leads from the
multi-function unit terminals and short circuit them in the connecting head
of the resistance thermometer. Measure the lead resistance by means of
a resistance bridge and change lead adjusting resistor (Ra) so that its
value is equal.

Resistance thermometer in 3-wire connection:

The resistance of each input lead must not exceed 30 [. No lead re-
sistance adjustment is necessary, provided that the resistances of the
input leads R

L

are equal. If necessary, they must be equalized by

means of a calibrating resistor.

Temperature difference 2 x Pt100

Range 850°C: X0 = -950°C; X100 = 950°C (

Type

=

2Pt100 85

)

Range 250°C: X0 = -250°C; X100 = 250°C (

Type

=

2Pt100 25

)

For lead resistance adjustment, the two thermocouples must be
short-circuited in the connecting head.
See also Page 35 .
With blinking

Set Dif

, wait until the input has settled

(minimum 6 s). Press M r

Cal done

is displayed r Lead resistance adjustment is finished. Remove the two

short-circuits.

Potentiometric transducer
Overall resistance ß 500 [ incl. 2 w RL.

Calibration or scaling is with the sensor connected.

+

Before calibration, the mains frequency required for operation must be adjusted.

Main menu r

Miscellaneous r Device data r Freque.

Calibration is as follows.

Calibration is as described in section 10.4. The user-specific calibration values are stored in configurations X0, X100.

Inputs

9499-040-82711

III-279

AINP1 ( analog input 1 (No. 08))