Emerson 4500 manual Calibration Overview

Rosemount 4500

Reference Manual

00809-0100-4027, Rev AA December 2005

Table 4-1. Recommended

Calibration Tasks

Transmitter Bench Calibration Tasks Field Calibration Tasks

4500_ G	1. Set output configuration parameters:	1.	Reconfigure parameters if necessary.
4500_ A	a. Set the range points.	2.	Perform low trim value section of the
	b. Set the output units.		full sensor trim procedure to correct for
			mounting position effects.
	c. Set the output type.
	d. Set the damping value.
	2. Optional: Perform a full sensor trim if
	equipment available (accurate pressure
	source required), otherwise perform the
	low trim value section of the full sensor
	trim procedure.
	3. Optional: Perform an analog output trim
	(Accurate multimeter required)

Calibration Overview

NOTE:

The transmitter performs to specification only when completely and correctly calibrated, including full sensor and analog output trim.

Complete calibration of the 4500 pressure transmitter involves the following tasks:

Configure the output parameters

•Set Process Variable Units (page 3-7)

•Set Output Type (page 3-8)

•Rerange (page 3-8)

•Set Damping (page 3-10)

Calibrate the sensor

•Full Trim (page 4-6)

•Zero Trim (page 4-6)

Calibrate the 4–20 mA output

•4–20 mA Output Trim (page 4-8); or

•4–20 mA Output Trim Using Other Scale (page 4-9)

Figure 4-1 on page 4-3illustrates 4500 transmitter data flow. Data flow can be summarized in four major steps:

1.A change in pressure is measured by a change in the sensor output (Sensor Signal).

2.The sensor signal is converted to a digital format that is understood by the microprocessor (Analog-to-Digital Signal Conversion).

3.Corrections are performed in the microprocessor to obtain a digital representation of the process input (Digital PV).

4.The Digital PV is converted to an analog value (Digital-to-Analog Signal Conversion).

4-2