Changes I would like to see made to Rockwell's Translate PLC-5 SLC utility

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Translate PLC-5 SLC 2.0 Step 0Having used Rockwell's Translate PLC-5 SLC utility on multiple occasions, and having discussed it's practical use with other programmers time and again, I recently sent the following recommendations to Rockwell:

INTs vs. DINTs

One of easier things I would like to see changed in the “Translate PLC-5 SLC 2.0 utility” is the automatic conversion of PLC-5 and SLC-500 INTs (integer data) to DINT’s (double integers.)

On first past, it would seem like a good idea to convert INT's to DINTs. But in certain applications the converted program won’t work if the former INT data files are converted to DINT's. So my recommendation is to give the user the option whether INT's should be converted to DINT's when they run the utility.

SCP Conversion

Translate PLC-5 SLC 2.0 Step 1While it's helpful to have SCP instructions converted, the resulting code gives most users a migraine.

The SLC-500 SCP instruction not only scales values, but also acts as a good visual aide displaying what the raw value is being scaled to. The converted code, while functionally accurate, is nowhere near as easy to decipher.

In fact, it's quite odd that after 14 years there's still no native SCP instruction for ladder logic in RSLogix 5000. That aside, since there has been an SCP add-on instruction available since the dawn of AOI's, why not allow the option to convert SLC-500 SCP’s to the Rockwell sample code version of the SCP AOI?

Long symbol names

The ability to import text and symbols from the PLC-5 and SLC-500 is valuable, but why is the utility limited with reguards to Symbol length? From a coding standpoint, it doesn't make sense to “truncate” long Symbol names since the Logix platform supports tag names much longer than any Symbol supported in APS, Ai, or RSLogix 500.

Translate PLC-5 SLC 2.0 Imported CodeIn large projects, when you truncate these names you end up with multiple tags with the same name. This is because most tag’s unique characters are often at the end of the tag name as opposed to the beginning (i.e. Plant1_Building1_Line1_Tank1 and Plant1_Building1_Line1_Tank2 both currently get truncated to the same name.)

Well those are my three recommendations for updating the Translate PLC-5 SLC 2.0 utility. If you've used it and have your own thoughts on how it could be made better, please share them with us here by leaving your comment in the “Leave a reply” form at the bottom of this page.


Shawn Tierney
Automation Blogger and Trainer

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