Emerson Rosemount 5900C, Reference Manual

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4.7 Calibration using WinSetup
The Calibrate function is a Rosemount TankMaster WinSetup tool that lets you adjust a
Rosemount 5900C 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 the 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 5900C with Still-pipe Array
Antenna. The radar propagation velocity is affected by the still-pipe. Based on the pipe
inner diameter, the Rosemount 5900C 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 Rosemount 5900C measurements along the still-pipe.
4.7.1 Hand dipping
Follow these instructions when you make hand dip measurements:
Prerequisites
Only one person should perform manual ullage measurements in order to guarantee good
repeatability between measurements.
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.
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.
Procedure
1. Hand dip until three consecutive readings within 1 mm are obtained.
2. Correct the tape according to the calibration record.
3. Note the hand dipped ullage and the gauge level reading simultaneously
4.7.2 Calibration procedure
Prerequisites
Do not calibrate when
• the tank is being emptied or filled
• agitators are running
• when there are windy conditions
• when there is foam on the product surface
The calibration procedure includes the following steps:
Reference Manual Configuration
00809-0100-5901 September 2019
Rosemount 5900C Radar Level Gauge 151