Emerson Rosemount 326P, Quick Start Manual

Page: 8 / 48

Figure 1-1: Hysteresis function Figure 1-2: Window function
• SP: Set point
• rP: Reset point
• P: Pressure
• Hy: Hysteresis
• Hno: Hysteresis function/normally open
• Hnc: Hysteresis function/normally closed
• FE: Window
• Fno: Window function/normally open
• Fnc: Window function/normally closed
1.3.2 Analog signal
The transmitter communicates measured pressure using an analog signal.
OU2 defines whether the set measuring range is provided as 4-20 mA (OU2 = I) or as 20-4
mA (OU2 = InEG).
Rerange the transmitter (set new values for ASP and AEP) by either manually entering
range points or with an applied pressure source.
• Applying a pressure source for the analog start point (tASP) or manually setting the
parameter (ASP) defines the measured value when the analog signal is 4 mA (20 mA at
InEG).
• Applying a pressure source for the analog end point (tASP) or manually setting the
parameter (ASP) defines the measured value when the output signal is 20 mA (4 mA at
InEG).
Minimum distance between ASP and AEP is 25 percent of the upper range limit (maximum
rangedown 4:1). For pressure range 3A, the minimum distance is 25 percent of the
measuring span.
Introduction Quick Start Guide
January 2019 00825-0100-4327
8 Quick Start Guide