IFM PI16 Series, Руководство по эксплуатации

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PI16xx PI18xx Electronic pressure sensor
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P = System pressure
HY = Hysteresis
FE = Window
4.6 Analogue output
The device provides an analogue signal proportional to the pressure. Within the measuring range the
analogue signal is between 4...20 mA. The measuring range is scalable:
• [ASP2] defines at which measured value the output signal is 4 mA.
• [AEP2] defines at which measured value the output signal is 20 mA.
Minimum distance between [ ASP2] and [ AEP2 ] = 20 % of the final value of the measuring
range.
If the measured value is outside the measuring range or in the event of an internal error, the current
signal indicated in the following figure is provided. The analogue signal in case of an error is
adjustable:
• [FOU] = On defines that the analogue signal goes to the maximum value (21.5 mA) in case of an
error.
MEW MAW AEP ASP
P -1,25 0 100 103,13
4
3,8
20
20,5
21,5
[mA]
FOU=On
1
2
4
UL OL
3
[% MEW]
Fig. 3: Output characteristics of the analogue output to Namur
1: Analogue signal
2: Measured value (in configured unit)
3: Measuring range (factory setting)
4: Scaled measuring range
P: Pressure
MAW: Initial value of the measuring range with non-scaled measuring range.
MEW: Final value of the measuring range with non-scaled measuring range
ASP: Analogue start point with scaled measuring range
AEP: Analogue end point with scaled measuring range
UL: Below the display range
OL: Above the display range
FOU: Output behaviour in case of an error
4.7 Customer-specific calibration
The customer-specific calibration changes the curve of measured values compared to the real
measured values (zero-point calibration and correction of gradient). Keep the following order:
u
Carry out zero calibration [coF] in the range -5%....+5% of final value of the measuring range
(VMR).