Really easy FactoryTalk View ME question

[Zlinger]

First time FTV user. So, I'm sure someone can answer this. It's probably already on this board somewhere, but maybe I just don't know how to search for it correctly.

I want to enter and display a timer preset in minutes (timer preset is milliseconds in the PLC). I'm using a numeric input cursor point object, and apparently I have no clue what I'm doing.

I'm a little confused why there is a value & optional expression field on the connections tab. Essentially, I want to send the input value times 60,000 to the PLC timer PRE, and display the timer PRE divided by 60,000. My syntax must be off or something. Any help is greatly appreciated.

 

[Zlinger]

Ok I figured it out. For anyone else reading this in the future and having the same problem, you need to enter this:

Value: "TAG"
Optional Exp: "?*60000"
Indicator: "TAG/60000"

 

[Operaghost]

<delete delete delete>

I was just typing it in too! Exactly the way you have it spelled out. Well done figuring it out

OG

 

[ASF]

There are a couple of other ways to skin that cat as well - you can write the minutes value to a DINT in the PLC and do the conversion into milliseconds in PLC logic, or you can set the connection up as a HMI tag, and then apply scaling to the tag. But the way you worked out is probably the most streamlined way I can think of!

 

[inJGS]

I use the tag in HMI in minutes and then I convert it to miliseconds in PLC:

MUL "MyTag" 60.000 "MyTimer.PRE"

 

[robertmee]

^Yes....I don't know what others do but I recommend never using the HMI to scale. Do the scaling in the PLC. So much easier to troubleshoot and easier to develop and implement the HMI. Just my 2c

 

[arlenjacobs]

^Yes....I don't know what others do but I recommend never using the HMI to scale. Do the scaling in the PLC. So much easier to troubleshoot and easier to develop and implement the HMI. Just my 2c

I also prefer to have all the data changes (expressions) in the PLC.

That makes it easier in the future if you need to replace that HMI, and the new one doesn't have the exact crazy feature you need.
IE. Numeric Input Cursor Point with optional write and read expressions.


...but, if you had to do a 100 of those in the PLC, might just be easier/faster to code it in the HMI. Who cares about the future?