Sensor Functions; Base Value And Factor; Smoothing; Limit Values - Ahlborn ALMEMO 2470-1S Operating Instruction

Sensor functions

11.1 Sensor functions
On a number of sensors, e.g. moisture content sensors, it may be necessary
before measuring to program correction values, i.e. base value or factor; for
measured values of an unstable, fluctuating nature smoothing would be advis-
able. This device - thanks to the clarity provided by its color display - is ideally
suitable for tasks with limit value monitoring. Limit values can also be pro-
grammed via the keypad.

11.1.1 Base value and factor

To display the electrical signal of a sensor as a
measured value with a physical quantity it is
nearly always necessary to perform zero-point
shift and multiplication by a factor. To perform
these steps the functions BASE and FACTOR
are provided. For a detailed description of
scaling, with an example, please refer to the
Manual, Section 6.3.11.
Displayed value = (measured value - BASE) x FACTOR
Entering base value ´BA´ and factor ´FA´ (see 9.3) Once the scaling values have
been programmed and the actual measured value thus modified, the correction
arrow appears in the status bar.

11.1.2 Smoothing

Measured values of an unstable or strongly
fluctuating nature, e.g. particularly turbulent
flows, should preferably be smoothed by
means of continuous averaging over a certain
time frame. The level of smoothing can be
set in the smoothing function ´DG´ by specifying
the number of measured values to be aver-
aged (range 2 to 99). (see 9.3)
Display with symbol

11.1.3 Limit values

The MAX limit value ´GH´ and the MIN limit
value ´GL´ can be programmed for each meas-
uring channel. (see 9.3) Hysteresis is normally
set to 10 digits but this can be adjusted to any
number between 0 and 99.(see Manual 6.2.7)
If limit values have been set but not exceeded,
the measured value is displayed in green.
Limit value overshot or undershot
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