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Are there special considerations when using an MVI69 module with an L20/L30 processor and can I use multiple MVI69 modules in the same rack?

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All MVI69 products you may use multiple modules within a CompactLogix rack with any processor but the l20 and l30 processor. The l20/30 processors only support up to 222 words for all I/O within that rack. Our MVI69 module will occupy 132 words of data (8 words of overhead + 62 words of input + 62 words of output (configured as 61 for the output configuration, but must round to the next even number for actual processor usage)).

If using an MVI69 with an l20/30 processor, you must set the block size to 60 words in the configuration file, and you may only use one MVI69 with that processor... This will also only leave 90 words for the rest of your I/O data. Rockwell has a unofficial utility called "CompactLogix backplane sizing utility" that will help estimate your I/O load with different modules. If using an l20 or l30 processor, then it is highly recommended to run this utility. You may download the utility by visiting the Allen Bradley website.<="">