Design And Function - ABB 265GS Operating Instruction

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Design and function

The 265A and 265G digital pressure transmitters are communication-ready field devices
featuring microprocessor-controlled electronics with multisensor technology.
For bidirectional communication, the devices have an FSK signal superimposed on the
4 ... 20 mA output signal (depending on their design) in accordance with the HART protocol; in
the case of devices that operate on a fully digital basis, communication takes place via the
PROFIBUS PA or FOUNDATION Fieldbus protocols, depending on their design.
The graphical user interface (DTM) can be used to configure, poll, and test the pressure
transmitter using a PC, depending on the relevant protocol. Communication using a handheld
terminal
protocol.
A control unit, consisting of two buttons for setting the "lower range limit value" and "upper
range limit value" parameters and a write protection switch, is available for "local" operation.
IMPORTANT (NOTE)
It is not possible to activate the write protection function via the control unit with the
FOUNDATION Fieldbus communication type.
The "local control unit" can be used in conjunction with a built-in LCD display for external
configuration and parameterization of the pressure transmitter, regardless of the selected
communication protocol.
As standard, the electronics housing features a finish that is resistant to aggressive
atmospheres. The process connection is made from stainless steel or Hastelloy C. The housing
cover and button unit may be leaded.
The name plate contains information about the design of the pressure transmitter. A full list of
the information on the name plate can be found in the previous section under "Name plate".
When making enquiries, always remember to quote the universally valid serial number (S/N)
and year specified.
IMPORTANT (NOTE)
In the case of explosion-proof designs, a description of the Ex design is also provided.
Barrel housings: On the name plate
DIN housings:
Another separate plate, located in front of the "local" control unit, describes the functions of the
three control elements using easily comprehensible symbols. In addition, a tag indicating the
measuring points may be attached (as an option).
1)
Communication / configuration / parameterization via handheld terminal / PC where type of protection "intrinsic
safety" applies:
In this case, the HHT / PC must be appropriately certified; this applies even if it is only connected for a short period
of time.
This proof of "intrinsic safety" must be supplied in addition to the transmitter.
With type of protection "flameproof enclosure Ex d", the handheld terminal must not be connected in a potentially
explosive atmosphere.
The HHT battery must not be replaced in a potentially explosive atmosphere.
IM/265Gx/Ax-EN-07
1)
is also possible, provided that the devices operate in accordance with the HART
On a separate plate
265Gx, 265Ax
Design and function
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