SMAR LD303, Инструкция по эксплуатации и техническому обслуживанию

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Configuration
3.27
Wait until the pressure value stabilizes and then actuates parameter UPPER until it reads 25.400.
For the lower value the procedure is the same, but we need to actuate in the parameter LOWER.
NOTE
Trim mode exit via local adjustment occurs automatically should the magnetic tool not be used
during some seconds.
Keep in that even when parameters LOWER or UPPER already present the desired value, they
must be actuated so that calibration is performed.
Limit Conditions for Calibration:
For every writing operation in the transducer blocks there is an indication for the operation associate
with the waiting method. These codes appear in parameter XD_ERROR. Every time a calibration is
performed. Code 16, for example, indicates a successfully performed operation.
Upper:
SENSOR_RANGE_EUO < NEW_UPPER < SENSOR_RANGE_EU100 * 1.25
Otherwise, XD_ERROR = 26.
(NEW_UPPER - PRIMARY_VALUE) < SENSOR_RANGE_EU100 * 0.1
Otherwise, XD_ERROR = 27.
(NEW_UPPER - CAL_POINT_LO) >CAL_MIN_SPAN * 0,75
Otherwise, XD_ERROR = 26.
NOTE
Codes for XD_ERROR:
16: Default Value Set;
22: Out of Range;
26: Invalid Calibration Request;
27: Excessive Correction.
Characterization Trim
NOTE
The calibration screens Characterization Trim of the Profibus View are similar to Simatic PDM
screens.
It is used to correct the sensor reading in several points.
Use an accurate and stable pressure source, preferably a dead-weight tester, to guarantee the
accuracy must be at least three times better than the transmitter accuracy. Wait for the pressure to
stabilize before performing trim.
The sensor characteristic curve at a certain temperature and for certain ranges may be slightly
nonlinear. This eventual non-linearity may be corrected through the Characterization Trim.
The user may characterize the transmitter throughout the operating range, obtaining even better
accuracy.
The characterization is determined from two up to five points. Just apply the pressure and tell the
transmitter the pressure that is being applied.
WARNING
The characterization trim changes the transmitter characteristics.
Read the instructions carefully and certify that a pressure standard with accuracy 0.03% or better
is being used, otherwise the transmitter accuracy will be seriously affected.
Characterize a minimum of two points. These points will define the characterization curve. The
maximum number of points is five. It is recommended to select the points equally distributed over
the desired range or over a part of the range where more accuracy is required.
The Figure 3.29 shows the window of Simatic PDM to characterize a new curve. Note that
FACTORY_CURVE_X indicates the applied pressure according to standard pressure source and
FACTORY_CURVEX_Y indicates measured pressure value to
LD303.