Ahlborn ALMEMO 2290-4 V5 - Scaling, Decimal Point Setting

6.6 Scaling, Decimal Point Setting
For indicating the electrical signal of a sensor as a measured value of a
physical variable it is, in most cases, necessary to set a decimal point shift, a
zero point shift and to perform a multiplication with a factor. The functions
EXPONENT ´EX´, BASE´BA´ and FACTOR ´FA´ are available for this. A detailed
description of the scaling, including an example, can be found in the manual
section 6.3.11.
Indicated value = (corrected meas. value - BASE) x FACTOR.
Decimal Point Setting
At first, the position of the decimal point should be checked and, by using the
EXPONENT, be adjusted to the required resolution and dimensioning of the
sensor, as required. The function EXPONENT ´EX´ allows for shifting the
decimal point as far to the left (-) or right (+) as it can be indicated on the
display.
Function EXPONENT ´EX´
Selection with key FUNCTION... Input see 5.4
1: 3 EX
Example: A force transducer with a 2.0000 V output should indicate 1000.0 N.
The decimal point must, via exponent 3, be shifted by 3 digits to the
right. The additionally required factor 0.5 can easily be calculated
from the new actual values 0.0 N and 2000.0 N. In this case, the
base value might only be required for a zero point correction.
Function BASE VALUE ´BA´
Selection with key F2... Input see 5.4
1: 0 0 1.2 BA
Function FACTOR ´FA´
Selection with key F2... Input see 5.4
1:0.5 0 0 0 FA
The arrow ´CORR´ will be indicated in the display if scaling values are
programmed and if the measured value is actually modified.
Two-Point Adjustment
The scaling values can be automatically determined by using a two-point
adjustment. First, the measured value is, at its 'zero state' (ice water,
unpressurized etc.), set to zero within the function MEAS. VALUE by using the
keys lo
ng, CLEAR (see 7.1.7).
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Sensor Programming