2600T Series Pressure transmitters |
OI/266/FF/ADD-EN Rev. B 17
– If this value doesn’t match the known Static Pressure applied in input at the transducer, enter the correct value in the
PRTB_STATIC_P_CAL_POINT_LO
and write to the transmitter. This writing executes an internal algorithm that produces the new
correction coefficients.
– Read again the
PRTB_STATIC_P_TRIMMED_VALUE
and check if its value now matches the real Static Pressure value
coefficients.
Static pressure high trimming (for piezo dP sensor only)
With this operation the
PRTB_STATIC_P_TRIMMED_VALUE
is automatically adjusted, in order to match the real value of Static
Pressure applied at the transducer in the upper part of the range. The following sequence of operations is required:
– Select the engineering unit of the measure in the
PRTB_STATIC_P_CAL_UNIT
(Pressure Unit Only)
– Read the Static Pressure value from the
PRTB_STATIC_P_TRIMMED_VALUE
.
– If this value doesn’t match the known Static Pressure applied in input at the transducer, enter the correct value in the
PRTB_STATIC_P_CAL_POINT_HI
and write to the transmitter. This writing executes an internal algorithm that produces the new
correction coefficients.
– Read again the
PRTB_STATIC_P_TRIMMED_VALUE
and check if its value now matches the real Static Pressure value.
Sensor temperature trimming
With this operation the
PRTB_SECONDARY_VALUE
(Sensor Temperature) is automatically adjusted, in order to match the real
value of the sensor temperature. The following sequence of operations is required:
– Select the engineering unit of the temperature in the
PRTB_SECONDARY_VALUE_RANGE_UNIT
(Temperature Unit Only)
– Read the Sensor Temperature value from the
PRTB_SECONDARY_VALUE.
– If this value doesn’t match the known Sensor Temperature of the transducer, enter the correct value in the
PRTB_SENSOR_TEMP_CAL_POINT
and write to the transmitter. This writing executes an internal algorithm that produces the
new correction coefficients.
– Read again the
PRTB_SECONDARY_VALUE
and check if its value now matches the real Sensor temperature value.
Parallel shift (P-dP)
In case the process (dp or p) cannot be led to 0 it is possible correct the measure performing the Parallel Shift operation. Typically
this operation is applicable for Level measurements.
Having the possibility to see/read the actual measure in percent, if it is not what expected, enter the percent of what the process
should measure. The correction consists in the shift of the calibration range values
PRTB_PRIMARY_VALUE_RANGE 0%
and
PRTB_PRIMARY_VALUE_RANGE 100%
in order to produce in output the measure,
PRTB_QUATERNARY_VALUE
at the
desired percentage. The parallel shift is executed by writing the desired percent value in the
PTRB_PARALLEL_SHIFT_PV
.
Important
After the parallel shift execution, the percent value of the
PRTB_QUATERNARY_VALUE
matches the desired percentage only if the
PRTB_LIN_TYPE
is
set to Linear. If an AI block is set to
CHANNEL = 4
it receives in input the
PRTB_QUATERNARY_VALUE
and in this case the
AI_OUT
matches the
desired percentage as well only if the
AI_L_TYPE
is set to Linear
This makes it possible to set the output signal of several
measuring devices that measure the same process variable to
the same value without having to perform a calibration with
applied pressure. E.G. the transmitter output can be adjusted
to gauge-glass for level measurement. This function can -
under the following circumstances - be carried out at any point
on the characteristic:
– Process variable within the adjusted measuring range -
transmitter with linear transfer function.
– Write protection on the transmitter must not be activated.
