Ahlborn ALMEMO 2590-2A, Руководство по эксплуатации

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13. Sensor programming
55
way as exceeding a measuring range limit or as sensor breakage). In the dis-
play, in front of the measured value affected, the appropriate arrow  or  ap-
pears and the alarm relays connected by relay cable are triggered (see 15.2).
Limit values can also have relays assigned to them (see 13.12.2). This alarm
status remains effective until the measured value returns within the prescribed
limit value by the amount set as hysteresis. Hysteresis is normally set to 10
digits but this can be adjusted to any number between 0 and 99 (see 14.7). The
event of a limit value being exceeded can also be used to start or stop a meas-
uring operation (see 13.12.2).
Function
Enter limit value, maximum (see 9.5):
7 Limit value, maximum: 123.4°C
Limit value, minimum :
7 Limit value, minimum : -----°C
To disable limit values :
<OFF>
To enable limit values : <ON>
13.6
Scaling, Decimal point setting
To display the electrical signal of a sensor as a measured value in its physical
size it is nearly always necessary to perform a zero-point shift and multiplication
by a factor. To perform these steps the functions BASE and FACTOR are pro-
vided. For a detailed description of scaling, with an example, please refer to the
Manual, Section 6.3.11.
Displayed value = (corrected measured value - BASE) x FACTOR
m
The FACTOR can be programmed within the
range -2.0000 to +2.0000. For factors below 0.2 or
above 2.0 an appropriate decimal point setting
should be used by entering the EXPONENT. Us-
ing EXPONENT the decimal point can be shifted
as far to the left (-) or to the right (+) as the display
permits. An exponential view of measured values
is not possible.
To calculate the scaling values automatically :
5 Base value: ------
5 Factor, Exponent : ------E0
the function menus (see 12.4) include, derived
from the actual values and setpoints, a special
menu
SCALING
.
Once the scaling values have been programmed and the actual measured value
thus modified the correction arrow appears indicating the measured value status
(see 9.2).
13.7
Correction values
Sensors can be corrected by means of the correction values ZERO-POINT and
GAIN; (see Manual 6.3.10).
Corrected measured value = (measured value - ZERO-POINT ) x GAIN