Endress+Hauser HART Proline Promass 83, Руководство по эксплуатации

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Operation Proline Promass 83
38 Hauser
5.3.3 Confirming error messages
For the sake of plant and process safety, the measuring device can be configured in such a
way that fault messages displayed (
$
) always have to be rectified and acknowledged locally
by pressing
F
. Only then do the error messages disappear from the display.
This option can be switched on or off by means of the "ACKNOWLEDGE FAULT MESSAGES"
function (see the "Description of Device Functions" manual).
!
Note!
• Fault messages (
$
) can also be reset and confirmed via the status input.
• Notice messages (!) do not require acknowledgment. Note, however, that they remain
visible until the cause of the error has been rectified.
5.4 Communication
In addition to local operation, the measuring device can be configured and measured values
can be obtained by means of the HART protocol. Digital communication takes place using the
4-20 mA current output HART.
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The HART protocol allows the transfer of measuring and device data between the HART
master and the field devices for configuration and diagnostics purposes. The HART master,
e.g. a handheld terminal or PC-based operating programs (such as FieldCare), require device
description (DD) files which are used to access all the information in a HART device.
Information is exclusively transferred using so-called "commands". There are three different
command groups:
There are three different command groups:
•
Universal Commands
Universal commands are supported and used by all HART devices. These are associated
with the following functionalities for example:
– Recognizing HART devices
– Reading digital measured values (volume flow, totalizer, etc.)
• Common practice commands:
Common practice commands offer functions which are supported and can be executed by
most but not all field devices.
• Device-specific commands:
These commands allow access to device-specific functions which are not HART standard.
Such commands access individual field device information, amongst other things, such as
empty/full pipe calibration values, low flow cut off settings, etc.
!
Note!
The measuring device has access to all three command classes.
5.4.1 Operating options
For the complete operation of the measuring device, including device-specific commands,
there are DD files available to the user to provide the following operating aids and programs:
!
Note!
• In the CURRENT RANGE function (current output 1), the HART protocol demands the
setting "4-20 mA HART" or "4-20 mA (25 mA) HART".
• HART write protection can be disabled or enabled by means of a jumper on the I/O board.
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HART handheld terminal Field Xpert
Selecting device functions with a HART Communicator is a process involving a number of
menu levels and a special HART function matrix.
The HART manual in the carrying case of the HART Communicator contains more detailed
information on the device.