scaling values using gx developer

Hey guys
I'm kinda struggling with gx developer and could do with a bit of guidance

essentially I have a register (say d10) which is being populated by a HMI. I need to scale this value up by multiplying it by 60000(i'm using it for a timer) then- I need to move this scaled up value into a timer (say T1)

Now...from what I've read gx developer doesn't have a scale command and some people say they convert it to a floating point first before multiplying it out.
Thing is...I aint exactly sure how to go about this and gx developer aint that user friendly.

Is it a matter of typing the formula straight in instead of a rung or something??

Any advice on any of the above is greatly appreciated

Damien

Since you need to multiply by 60000, it appears you are using a 1ms timer to time in increments of 1 minute. If so, you might try using a 1 minute timer to increment a register, then compare that register to your HMI value to know when 'x' minutes has elapsed.

I'm not sure which PLC you have, but see if it has 10ms resolution timers available (T200-T245 on the FX1N), so you can use a (more reasonable) value of 6000 to get 1 minute.



-Eric

Eric Nelson said:

Since you need to multiply by 60000, it appears you are using a 1ms timer to time in increments of 1 minute. If so, you might try using a 1 minute timer to increment a register, then compare that register to your HMI value to know when 'x' minutes has elapsed.

-Eric

Click to expand...

Huh....what a great idea! I really have no idea what these PLC's can do it seems. I had to look up the compare instruction but it seems like a much easier way of going about this alright. You are quite right in assuming I am using a 1 min timer.

I'm just wondering...how would I set up the increment command to increment by one every time the timer passes the 1min mark?

I guess I could use a compare instruction on the timer to increment a register by one pulse every time it matches k60000(1min) constant. or is there a smarter way of doing this??

Thanks again for the help!

t25fan said:

Huh....what a great idea! I really have no idea what these PLC's can do it seems. I had to look up the compare instruction but it seems like a much easier way of going about this alright. You are quite right in assuming I am using a 1 min timer.

I'm just wondering...how would I set up the increment command to increment by one every time the timer passes the 1min mark?

I guess I could use a compare instruction on the timer to increment a register by one pulse every time it matches k60000(1min) constant. or is there a smarter way of doing this??

Thanks again for the help!

Click to expand...

This is an example of a down time counter using 1 timer to increment each second, and from there incrementing counters for minutes and hours. Hope it helps.

Dave

Hi

By using dploof23 example just change the K value in to the min counter. Leave the min timer alone and this way when your counter is done no mater what value you put into you c20 D20 say you will always use xic c5 and your time is done.

I taught there was a D reg that you could change in GX to change the time range of some timers, not sure but I think i remember it from way back when
as we say in Ireland "When God was a young fellow"


Donnhadh

Donnchadh said:

Hi

By using dploof23 example just change the K value in to the min counter. Leave the min timer alone and this way when your counter is done no mater what value you put into you c20 D20 say you will always use xic c5 and your time is done.

I taught there was a D reg that you could change in GX to change the time range of some timers, not sure but I think i remember it from way back when
as we say in Ireland "When God was a young fellow"


Donnhadh

Click to expand...

The time range depends on the PLC type. In the FX series it depends on the number of the timer used. I attached the section from the FX3U programming manual.

Dave

Thanks dploof23 and Donnhadh. I'll take another look at this now. some good ideas and reference material on this site I really appreciate all the help.

Damien

Hi

No bother your welcome,

Don't forget to come back and update us to see how you get on
As it may help someone else in the future

Donnchadh