Emerson Rosemount 326P, Быстрый старт

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Figure 1-3: Factory setting Figure 1-4: Transmitter reranged
P: system pressure
MAW: initial value of the measuring range (Lower range limit [LRL])
MEW: final value of the measuring range (Upper range limit [URL])
1: OU2 = I
2: OU2 = InEG
In the set measuring range the output signal is between 4 and 20 mA (OU2 = I) or between
20 and 4 mA (OU2 = InEG). When pressure is outside the set measuring range, the output
signal is as follows:
• System pressure above the measuring range:
— Output signal > 20 mA if OU2 = I.
— Output signal 4 to 3.8 mA if OU2 = InEG.
• System pressure below the measuring range:
— Output signal 4 to 3.8 mA if OU2 = I.
— Output signal > 20 mA if OU2 = InEG.
1.3.3 Customer-specific calibration (sensor trim)
A customer specific calibration (sensor trim) corrects the pressure offset and pressure
range to match a pressure standard. This provides a slope correction to the transmitter's
current characterization curve. An accurate pressure standard is required for a full
calibration. For more information on performing a Sensor Trim, see
Perform a sensor trim .
• Sensor Trim is a two-point sensor calibration that applies two end-point pressures
(CP1, CP2) then linearizes the output between them. CP1 and CP2 must be within the
scaled measuring range. For more information, see
Analog signal .
• Zero trim is a single-point offset adjustment. It compensates for mounting position
effects and is most effective when performed with the transmitter installed in its final
Quick Start Guide Introduction
00825-0100-4327 January 2019
Quick Start Guide 9