Please HELP!
I need to know whats better and why...Tags or Commands

Specific Pros and Cons - (Loss/Gain) Between Message Commands and Producer/Consumer Tags

 

Neither is "better." It's a question of preference, really.

Pros of Produced / Consumed
(a) Repeatable, known performance. You want 50ms updates, you get 50ms updates. (Plus some jitter, obviously, but it'll be pretty darn close.)

(b) No ladder logic. Just configure and go.

Cons of Produced / Consumed
(a) Generally have to download to make any changes.

(b) No ladder logic means when it's not working you really can't tell WHY it's not working.

Pros of Message Commands
(a) It's in ladder logic, so it can be easier to troubleshoot a problem.
(b) Can make changes without having to redownload the project.

Cons of Message Commands
(a) You have to include it in ladder logic.

(b) You have no idea how long it's going to take.

(c) You have no idea if a "write" command really truly worked, and the written-to processor has no idea what's coming where.

(d) You can accidentally overwrite data willy-nilly.

-James Ingraham
Sage Automation, Inc.