Cameron Scanner 2000 microEFM, Руководство пользователя по оборудованию

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C-10
Appendix C Scanner
®
2000 microEFM
Device Description
The device description (DD) is a text file that precisely describes Scanner 2000 device capabilities for use
by the host system. It defines the parameters that are available for building control loops, establishes the
arrangement of parameters in a menu structure, and determines how parameters are related to one another.
DD files are downloaded to the host in preparation for configuring the device. These files are available on the
Fieldbus Foundation™ website (www.fieldbus.org) and the Cameron website (www.c-a-m.com/flo). There are
two device description files and one capabilities file (CFF). All three files must be downloaded in order for the
host to identify the Scanner 2000 as a networked device.
Note Device description files are available in both DD4 and DD5 formats. Please confirm the compatibility
of your host system before selecting a version for download. DD4 files have extensions .ffo and .sym,
and DD5 files have extensions .ff5 and .sy5.
Block Descriptions
The Scanner 2000 fieldbus module contains six blocks:
•
a resource block
• a transducer block
• 4 analog input function blocks
Each block is identified by a tag name. The user can change the tag name, however, the name must be unique
in the system. A tag name can contain up to 32 characters.
Block Modes
Each block has a block mode (MODE_BLK) parameter that determines the block’s mode of operation. Four
elements make up the block mode: Target, Actual, Permitted and Normal.
• The Target setting is the desired operating mode.
• The Actual setting is the current mode of operation and is read-only. An Actual mode that differs from the
Target mode should be investigated. See the BLOCK_ERR parameter for more information.
• The Permitted setting determines the mode options that may be selected as the Target mode.
•
The Normal setting is a reminder of the normal operating mode that the block should be returned to in the
event that the mode is changed, either by a user or as the result of operating conditions.
Typically, blocks are placed either in Auto mode or Out of Service (OOS) mode. For the Scanner 2000, the
standard mode of operation for the resource and transducer blocks is Auto and this setting is entered as the
“target” mode. When the mode is changed to OOS, the blocks become inoperable. Some online configuration
changes to the transducer block can be made only when the block is in OOS mode.
Resource Block
The resource block can be used to check hardware status, to disable all function blocks in the Scanner 2000,
and to restart the control strategy execution. It has no input or output parameters and cannot be linked to
another block.
Important The resource block mode controls the mode of all other blocks. When the resource mode
is OOS, the modes of all other blocks are placed in OOS mode, effectively disabling the
entire device. Auto is the normal operating mode of the resource block.