Ahlborn ALMEMO 2290-2/3, Руководство по эксплуатации

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For some sensors special functions are available in this context:
1
.
With pH probes , if the two keys
START/STOP
and
F2
dare pressed during switch-on,
the locking is only temporary, i.e. until the device is switched off and set to 3. An
undesired adjustment can then be avoided.
2. Dynamic pressure probes are very delicate and should be adjusted in an
unpressurized state before each use (i.e. disconnected hoses or Pitot tube out of
flow). The correction value must be entered before the conversion
'pressure-to-velocity' is performed. For the ranges L840 and L890 an adjustment is
possible even if the channel is locked. The zero point error is temporarily being
written into the internal calibration offset until the switch-off is performed.
3. With the following sensors, a slope adjustment is performed in the same way for
the corresponding calibration value:
pH probe: pH4 or pH10
Conductivity: 2.77mS/cm (FY A641-LF) or 147µS/cm (FY A641-LF2)
O
2
saturation: 101% (FY A640-O2)
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 zero point shift and to
perform a multiplication with a certain factor. The functions BASE ´
BA
´,
FACTOR ´
FA
´ and EXPONENT ´
EX
´ 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 measured value - BASE) x FACTOR.
Function BASE VALUE ´
BA
´
Select by using the key F2 ... Input see 5.4
1:- 7.0 0
BA
Function FACTOR ´
FA
´
Select by using the key
F2...
Input see 5.4
1:-.1 6 3 8
FA
Function EXPONENT ´
EX
´
Select by using the
F2...
Input see 5.4
1: 2
EX
The arrow CORR will be indicated in the display if scaling values are
programmed and if the measured value is actually modified.
Decimal Point Setting
The FACTOR can be programmed in the range -2.0000 to +2.0000. For factors
over 2.0 or under 0.2 a corresponding decimal point setting must be
considered by entering the EXPONENT. The function EXPONENT ´
EX
´ allows
to shift the decimal point to the left (-) or right (+) as far as it can be indicated
26 ALMEMO

2290-2/3
Sensor Programming