Calibration Using Winsetup - Emerson Rosemount 5900S Series Reference Manual

Reference Manual
00809-0100-5900, Rev CA
June 2014
4.7 CALIBRATION
USING WINSETUP
Section 4. Configuration
The Calibrate function is a TankMaster WinSetup tool that lets you adjust a
Rosemount 5900S level gauge in order to minimize the offset between actual
(hand dipped) product levels and the values measured by the level gauge. By
using the Calibrate function you can optimize measurement performance over
the whole measurement range from the top to the bottom of the tank.
The Calibration function calculates a Calibration Distance based on fitting a
straight line to the deviations between hand dipped levels and levels
measured by the transmitter.
The Calibration function is specially suitable for a Rosemount 5900S with
Still-pipe Array Antenna. The radar propagation velocity is affected by the
still-pipe. Based on the pipe inner diameter, the 5900S automatically
compensates for the pipe influence. Since the average pipe diameter may be
difficult to determine accurately, a minor calibration is often needed. The
Calibrate function automatically calculates a Correction Factor in order to
optimize the 5900S measurements along the still-pipe.
Procedure
The adjustment process includes the following steps:
1. Record the hand dipped ullage values and the corresponding values
measured by the level gauge.
2. Enter the hand dipped level values and the level gauge values into the
WinSetup Calibration Data window (see "To enter calibration data" on
page 4-31).
3. Inspect the resulting calibration graph and, if necessary, exclude
measurement points which should not be used in the adjustment
calculation.
Required information
Make sure that the following information is available when you intend to use
the Calibrate function in TankMaster WinSetup:
• A list of hand dipped ullage values.
• A list of level values measured by the 5900S that correspond to the
hand dipped ullage/level values.
Hand dipping
Staff
Only one person should perform manual ullage measurements in order to
guarantee good repeatability between measurements.
Hand dip tape
Use only one tape for the calibration. The tape should be made of steel
and calibrated by an approved testing institute. It must also be free from
bends and kinks. The thermal expansion factor and calibration
temperature shall also be provided.
Dip hatch
A dip hatch should be available close to the level gauge. If the dip hatch is
far away from the level gauge, differences in roof movements may result in
large errors.
Rosemount 5900S Series
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