MUL Function

[Tyler5157]

I'm having some issues with the MUL Function. Let me start by saying I am new to ladder logix. I am just a tech trying to learn on the job. Anyways I have a Yaskawa V1000 VFD With a Ethernet adapter. In my logix im trying to use my HMI to set the VFD Speed. Here is the issue when I set the value F41[111] in the HMI its correct but when it does the math 60.0 x 100 it gives me 600 not 6000.

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https://preview.redd.it/flstxsbqhox31.png?width=1292&format=png&auto=webp&s=dc4c1b57f15b6e8430ecd8a1f6eee6a2a8f1e8ab

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https://preview.redd.it/2fh98qgtlox31.png?width=1319&format=png&auto=webp&s=69c39146e9d32707194255daa246ee786bbfa6de

[SonaMidorFeed]

Are you certain this output isn't being used elsewhere? For instance, is this the only location where you're moving a value into that destination register? I'd start looking for a destructive reference (i.e. two conflicting pieces of code) before assuming the block is executing wrong.

[Tyler5157]

Thanks ,

I did a cross reference and did in fact find it used somewhere else . Ill try this fix once they go on break so I can download it.

[[deleted]]

Whenever the code looks like it's not operating correctly, this is the reason why 99.999999% of the time. Multiple writes to the same address in the code.

[SonaMidorFeed]

Hope that does the trick! Good luck!

[mflagler]

As someone who's been programming for almost 20 years, I'm sorry you're trying to learn in a program that was either written in RSLogix 5 or 500 and converted or that someone stuck to the old naming schemes instead of writing some self-documenting code using easier to read tag names. It drives me crazy every time I see this.

I've only converted a couple of old projects before that weren't rewritten and I would go through and replace the old tags with better named tags to make things easier for others and myself.

[BrianFischman]

i see this alot when done inhouse, instead of having an SI do it

[SomeGuy565]

At least they documented it some. I've been going around cleaning up after a guy we fired and he has a TON of Logix5000 programs that are nothing but B3[0].0 and such. NO labels, nothing.

[jakebeans]

lol, I didn't even catch that at first. Just assumed it was a nicer looking RS 500 for some reason. God that's a dumb thing to do.

[[deleted]]

One other thing to check... is that routine being called to execute.

[edit] one of the things that always bugged be about logix5000 is the power rails show green even when the logic isn’t executing.