Dynisco IPX II Series, Руководство по эксплуатации

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FUNCTION
also available including Hastelloy C-276 which has excellent corrosion resistant properties (but is not
good for abrasion). For other materials please consult the factory.
Behind the lower diaphragm is a capillary tube filled to the upper diaphragm. As the process
pressure deflects the lower diaphragm, the fill is displaced through the capillary tube to deflect the
upper diaphragm.
The upper diaphragm has a 5000 ohm thin film strain gage element deposited on it in the
configuration of a Wheatstone Bridge. The deflection of the upper diaphragm causes a change in the
resistance of the strain gage and hence a change in the balance of the bridge. The amount of
imbalance is directly proportional to the applied pressure. This completes the translation of pressure
applied to the lower diaphragm into a usable electrical signal.
4.2.3 4.2.3 4.2.3 4.2.3 4.2.3 E E E E E
L E L E
L E L E L ECTRICAL
CTRICAL
CTRICAL CTRICAL CTRICAL
The low level output signal from the bridge is amplified via an instrumentation amp circuit. The
amplified signal then goes to the input of the analog-to-digital (A/D) converter.
Once the microprocessor has the converted voltage input from the A/D converter, the compensation
algorithms are executed. The unit is compensated for any errors introduced by temperature effects on
the gauge, snout electronics, and the nonlinearities of the pressure measurement itself. The corrected
digital signal is sent to a digital-to-analog (D/A) converter which modulates the current of the unit’s
power supply between 4 and 20 milliamps for an output current proportional to the applied
pressure.
Fig. 4- Fig. 4-
Fig. 4- Fig. 4-
Fig. 4-2 2
2 2
2 Functioning Principle of the PT of the IPX II Series Functioning Principle of the PT of the IPX II Series
Functioning Principle of the PT of the IPX II Series Functioning Principle of the PT of the IPX II Series
Functioning Principle of the PT of the IPX II Series