Function And System Design; Components Of The Pressure Transmitter; Product Description; Measuring Range Limits And Span Limits - ABB 2600T Series Operating Instruction

7

Function and system design

Change from two to one column
7.1

Components of the pressure transmitter

Fig. 3: Device overview
Change from one to two columns
7.2

Product description

The 266Jxx/266Cxx multivariable pressure transmitters
measure the mass flow of gases, vapors, and liquids in
accordance with the differential pressure procedure and the
level of the liquids in the process industry. These transmitters
supply an analog or digital output signal. Simultaneously and
with high accuracy they measure differential pressure, static
pressure and with a Pt100 in 4-conductor technology, they
also measure the process temperature. The differential
pressure measuring ranges are scaled from 1 to 2000 kPa.
The measuring ranges for static pressure are 0.6 to 2, 10 and
41 MPa. The transmitters can be overloaded on one side to
the respective upper measuring range value of the static
pressure.
7.3

Measuring range limits and span limits

The data sheets for the Series 2600T multivariable transmitters
contain all the information concerning the measuring range
and measuring span of the individual models, as well as the
sensor code.
12 OI/266CXX/266JXX/HART-EN Rev. B | 266CRx, 266JRx, 266CSx, 266JSx
The following terminology is used for the different parameters:
URL: Upper Range Limit of a specific sensor. The highest
measured value that can be measured by the
transmitter.
LRL: Lower Range Limit of a specific sensor. The lowest
measured value that can be measured by the
transmitter.
URV: Upper Range Value The highest measured value to
which the transmitter is calibrated.
LRV: Lower Range Value. The lowest measured value to
which the transmitter is calibrated.
SPAN: Measuring span. The algebraic difference between the
start of the measuring range and the end of the
measuring range. The smallest span is the smallest
value that can be selected without impairing the
specified measuring accuracy.
TURN DOWN Span ratio The ration between the maximum span and
RATIO: the calibrated span.
The measuring transmitter can be calibrated to any measuring
range between LRL and URL with the following restrictions.
— LRL ≤ LRV ≤ (URL - CAL SPAN)
— CAL SPAN ≥ MIN SPAN
— URV ≤ URL