Emerson Rosemount 5900S Series, Справочное руководство

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4.10 General block information
4.10.1 Modes
Changing modes
To change the operating mode, set the MODE_BLK.TARGET to the desired mode. After
a short delay, the parameter MODE_BLOCK.ACTUAL should reflect the mode change if the
block is operating properly.
Permitted modes
It is possible to prevent unauthorized changes to the operating mode of a block. To do
this, configure MODE_BLOCK.PERMITTED to allow only the desired operating modes. It is
recommended to always select OOS as one of the permitted modes.
Types of modes
For the procedures described in this manual, it will be helpful to understand the following
modes:
AUTO The functions performed by the block will execute. If the block has any
outputs, these will continue to update. This is typically the normal
operating mode.
Out of
Service
(OOS) The functions performed by the block will not execute. If the block has any
outputs, these will typically not update and the status of any values passed
to downstream blocks will be “BAD”. To make some changes to the
configuration of the block, change the mode of the block to OOS. When
the changes are complete, change the mode back to AUTO.
MAN In this mode, variables that are passed out of the block can be manually set
for testing or override purposes.
Other
types of
modes Other types of modes are Cas, RCas, ROut, IMan and LO. Some of these
may be supported by different function blocks in the Rosemount 5900S.
For more information, see the Function Block manual (Document No.
00809-0100-4783).
Note
When an upstream block is set to OOS, this will impact the output status of all
downstream blocks. The figure below depicts the hierarchy of blocks:
Figure 4-15: Hierarchy of Blocks
$ % & '
A. Resource Block
B. Transducer Block
C. Analog Input (AI Block)
D. Other function blocks
Configuration Reference Manual
September 2019 00809-0100-5900
138 Reference Manual