LD303 - Operation and Maintenance Instruction Manual
3.24
Lower and Upper Trim
NOTE
The calibration screens of lower and upper value of the Profibus View are similar to Simatic PDM
screens.
Each sensor has a characteristic curve that establishes a relation between the applied pressure and
the sensor signal. This curve is determined for each sensor and it is stored in a memory together
with the sensor. When the sensor is connected to the transmitter circuit, the content of its memory is
made available to the microprocessor.
Sometimes the value on the transmitter display and transducer block reading may not match the
applied pressure.
The reasons may be:
x
The transmitter mounting position.
x
The user's pressure standard differs from the factory standard.
x
The transmitter had its original characterization shifted by over pressurization, over heating or
by long term drift.
The
TRIM
is used to match the reading with the applied pressure.
There are two types of trim available:
Lower Trim
: It is used to trim the reading at the lower range. The operator informs the
LD303
the
correct reading for the applied pressure. The most common discrepancy is the lower reading.
NOTE
Check on section 1 the note on the influence of the mounting position on the indicador.
For better accuracy, the trim adjustment should be made in the in the lower and upper values of
the operation range values.
Upper Trim
: It is used to trim the reading at the upper range. The operator informs the correct
reading to
LD303
for the applied pressure.
For best accuracy, trim should be done at the operating range. The figures 3.26 to 3.29 show the
trim adjustment operation.
Pressure Trim - LD303
NOTE
The calibration screens Pressure Trim of the Profibus View are similar to Simatic PDM screens.
Via Simatic PDM
It is possible to calibrate the transmitter by means of parameters CAL_POINT_LO and
CAL_POINT_HI.
First of all, a convenient engineering unit should be chosen before starting the calibration. This
engineering unit is configured by SENSOR_UNIT parameter. After its configuration the parameters
related to calibration will be converted to this unit. Then, select Zero/Lower or Upper calibration
menu.
Содержание LD303
Страница 1: ...Profibus PA Pressure Transmitter L D 3 0 3 M E...
Страница 8: ...LD303 Operation and Maintenance Instruction Manual VIII...
Страница 15: ...Installation 1 7 Figure 1 1 f Dimensional Drawing and Mounting Position Sanitary Transmitter with Extension...
Страница 22: ...LD303 Operation and Maintenance Instruction Manual 1 14...
Страница 26: ...LD303 Operation and Maintenance Instruction Manual 2 4...
Страница 49: ...Configuration 3 23 Figure 3 24 Block Mode for Totalizer Block Figure 3 25 Set Reset for Totalizer Block...
Страница 74: ...LD303 Operation and Maintenance Instruction Manual 4 6 Figure 4 4 Exploded View...
Страница 83: ...Maintenance Procedures 4 15 Figure 4 8 TPE Software Screen...
Страница 102: ...LD303 Certifications Information A 4 CSA NEMKO and EXAM CEPEL NEPSI...
Страница 104: ...LD303 Certifications Information A 6 CEPEL...
Страница 105: ...Appendix A A 7 Control Drawing Factory Mutual FM...
Страница 106: ...LD303 Certifications Information A 8...
Страница 108: ...LD303 Operation and Maintenance Instruction Manual B 2...