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GeneralRe: Ladder Logic any experts here? Pin
fgs196321-Mar-24 6:21
fgs196321-Mar-24 6:21 
GeneralRe: Ladder Logic any experts here? Pin
glennPattonWork321-Mar-24 22:19
professionalglennPattonWork321-Mar-24 22:19 
GeneralRe: Ladder Logic any experts here? Pin
Nelek21-Mar-24 20:53
protectorNelek21-Mar-24 20:53 
AnswerRe: Ladder Logic any experts here? Pin
Ralf Meier21-Mar-24 9:16
mveRalf Meier21-Mar-24 9:16 
GeneralRe: Ladder Logic any experts here? Pin
glennPattonWork321-Mar-24 10:16
professionalglennPattonWork321-Mar-24 10:16 
GeneralRe: Ladder Logic any experts here? Pin
Ralf Meier21-Mar-24 10:29
mveRalf Meier21-Mar-24 10:29 
GeneralRe: Ladder Logic any experts here? Pin
glennPattonWork321-Mar-24 10:43
professionalglennPattonWork321-Mar-24 10:43 
GeneralRe: Ladder Logic any experts here? Pin
fgs196322-Mar-24 4:04
fgs196322-Mar-24 4:04 
glennPattonWork3 wrote:
the ladder appears inside function blocks (which confused me!)
It's actually pretty cool and very functional (pardon the pun). It's been like this for decades so Siemens was actually ahead of the curve compared to many PLCs. Here are a few basics that might help.

OB1 is the "main" cyclic function that loops endlessly.
OB100 is a "first scan" function that runs one time at PLC power-on before OB1 starts looping.
OB## are interrupt functions that only occur when a fault occurs (hardware or software).
FC## are functions with inputs and outputs but no internal storage
FB## are functions with inputs, outputs and internal persistent storage (called STATS)
DB## are data blocks that maintain persistent storage. Every FB call requires an associated DB but DBs can also stand alone.

With "Multi-Instance" calls you can call an FB multiple times. Each instance has it's own unique inputs, outputs and DB (persistent storage). Think of it as a class in C++.
GeneralRe: Ladder Logic any experts here? Pin
Nelek21-Mar-24 20:50
protectorNelek21-Mar-24 20:50 
GeneralRe: Ladder Logic any experts here? Pin
glennPattonWork321-Mar-24 22:23
professionalglennPattonWork321-Mar-24 22:23 
GeneralRe: Ladder Logic any experts here? Pin
Nelek21-Mar-24 23:08
protectorNelek21-Mar-24 23:08 
GeneralRe: Ladder Logic any experts here? Pin
mark.shultz@controlss.com22-Mar-24 5:33
mark.shultz@controlss.com22-Mar-24 5:33 
GeneralRe: Ladder Logic any experts here? Pin
petechic25-Mar-24 3:12
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GeneralRe: Ladder Logic any experts here? Pin
glennPattonWork325-Mar-24 10:28
professionalglennPattonWork325-Mar-24 10:28 
GeneralRe: Ladder Logic any experts here? Pin
petechic25-Mar-24 10:40
petechic25-Mar-24 10:40 
GeneralLatest Alien movie - teaser trailer Pin
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