Emerson 8800C User Manual

3-5
Operation
D/A Trim D/A Trim (Digital-to-Analog Trim) enables you to check and trim
the analog output in a single function. If the analog output is trimmed,
it will be scaled proportionally through the range of the output.
To trim the digital-to-analog output, initiate the D/A Trim function and
connect an ammeter to the loop to measure the actual analog output of
the meter. Follow the on-screen functions to complete the task.
Scaled D/A Trim Scaled D/A Trim enables you to calibrate the flowmeter analog output
using a different scale than the standard 4-20 mA output scale.
Non-scaled D/A Trimming (described above), is typically performed
using an ammeter where calibration values are entered in units of
milliamperes. Both non-scaled D/A trimming and scaled D/A trimming
allow you to trim the 4-20mA output to approximately ±5% of the
nominal 4mA end point and ±3% of the nominal 20mA end point.
Scaled D/A Trimming allows you to trim the flowmeter using a scale
that may be more convenient based upon your method of measurement.
For example, it may be more convenient for you to make current
measurements by direct voltage readings across the loop resistor. If
your loop resistor is 500 Ohms, and you want to calibrate the meter
using voltage measurements made across this resistor, you could
rescale (select CHANGE on the 275) your trim points from 4-20mA to
4-20mA x 500 ohm or 2-10 VDC. Once your scaled trim points have
been entered as 2 and 10, you can now calibrate your flowmeter by
entering voltage measurements directly from the voltmeter.
Shed Freq at URV Shed Freq at URV function gives the shedding frequency
corresponding to your URV.
BASIC SETUP The Model 8800C must be configured for certain basic variables in order
to be operational. In most cases, all of these variables are pre-configured
at the factory. Configuration may be required if your Model 8800C is not
configured or if the configuration variables need revision.
Tag Tag is the quickest way to identify and distinguish between
flowmeters. Flowmeters can be tagged according to the requirements of
your application. The tag may be up to eight characters long.
Service Type The flowmeter can be used for liquid or gas/steam applications, but it
must be configured specifically for the application. If the flowmeter is
not configured for the proper service type, readings will be inaccurate.
Select the appropriate Service Type for your application:
• Liquid
• Gas/Steam
HART Comm. 1, 2, 5
HART Comm. 1, 2, 6
HART Comm. 1, 2, 7
HART Comm. 1, 3
HART Comm. 1, 3, 1
HART Comm. 1, 3, 2

Emerson 8800C Specifications

General

Brand	Emerson
Model	8800C
Category	Measuring Instruments
Language	English