A loop block is a CAD drawing block with macros that retrieve data from all instrument tags of a specific loop. Because a loop block is a single template block file, you do not need to specify insertion points for this block. You need to create loop blocks in your CAD application and modify the macros as appropriate. Then, in Smart Instrumentation, in the Drawing Block Types > Loop Block folder of the Domain Explorer, you define loop blocks you want to make available for association with loop numbers. After that, you can associate the loop blocks with loop numbers displayed in the Loops folder of the Domain Explorer.
You define loop blocks and manage their properties in the same way as you do with instrument blocks. You can only assign one loop block to a particular loop. You can also assign the same loop block to more than one loop. Therefore, when duplicating a loop that already has a loop block assigned, the software also duplicates the loop block for the duplicated loop.
In loop drawing generation, the loop block has the highest generation priority. The software ignores the instrument blocks when generating a loop drawing if the source loop has a loop block and also blocks assigned to the loop instruments via the instrument type using the automatic block assignment method.
The loop block macro structure is MACRO.<macro function>.<instrument type>.<tag suffix>, where each segment of the macro structure is described as follows:
MACRO
This segment denotes an existing macro used by Smart Instrumentation in CAD loop drawing generation. A loop block macro definition can be either MACRO, MACRO.X, or MACRO.X.Y if the macro requires additional parameters.
Macro function
This is an optional segment displaying the macro function name, for example, TRIM.
Instrument type
This is a required segment that denotes the instrument type abbreviation of a loop tag, for example, FT, FE, and so forth.
Tag suffix
This segment denotes the suffix identification defined in the instrument naming convention. This segment is only required if a loop includes more than one instrument with the same instrument type.
The following are examples of loop block macros:
TAG_MOD_DESC.FE
The instrument model description for the flow element in the loop.
TERM_NUM.1.3.FT.B
The terminal name of the first termination of the wire level 3 for the second (Suffix B) flow transmitter in the loop.
TAG_NUM.s54.LSHH
Four characters of the level switch name starting from the fifth character, as defined in the s54 macro function. For example, if the tag number is 101-LSHH -100, the macro retrieves LSHH.