TWIDO PLC... Retain Value

Hi All...
I am trying to set initial values to memory words inside a TWIDO PLC, and i had an answer from someone before that it could be done through simulation, but i am still not getting them when i simulate the program.. Could i have more details about that???
Also for Retaining values, in the help they are mentioning a system Bit to do it but i do not seem to be able to use it correctly?

May i have more details about both subjects.. (INITIAL and Retain) values??
Thanks

Anything Guys

during ''debuging'', i found a place ''manage Animation table'' where you can write the initial value (write value from latch) this copie the value from the retained colunn to the plc data register

but the problem is that each time i download the plc, these value return to 0 and i need to manually execute this again...

i'm also looking for a better way to manage that

i need initial value that can be managed by the hmi later and if the battery goes out, to start again with the initial value instead of 0

Yes this is the problem, i am not sure that it will return back to its initial state...

There is a system bit that runs for the first scan only to put the initial values inside, but still the retain values is not working, i mean when the user change the value can the plc save this value or not?

There are also system bits %S95 and %S96, but i am not sure how can i use them to retain many values, lets say 4 or 5 values...

Please help

eyad267 said:

Yes this is the problem, i am not sure that it will return back to its initial state...

There is a system bit that runs for the first scan only to put the initial values inside, but still the retain values is not working, i mean when the user change the value can the plc save this value or not?

There are also system bits %S95 and %S96, but i am not sure how can i use them to retain many values, lets say 4 or 5 values...

Please help

Click to expand...

Why don't you add a couple of lines of code that will move the desired hard coded values from the holding location (registers) to the working registers on "First scan" or initial unit power up.
During normal operation, move the contents of the 4-5 working registers to the holding location.
Haven't touched a twido but all PLCs pretty much support the first scan solution.

the only problem with the first scan is that the data are overwriten each time the plc is powered down and up again

with better plc, there is an automatic function to get some initial value forced just if plc lost is memory....

for a simple exemple in a start and stop pump function according to a water level, you can preset at factory start and stop level that work and that can also be changed at hmi during commissionning. If something bad happend like lost of power for a very long time to discharge plc battery, On the next power up, the sp return to the factory set ones instead of 0.....0 = nothing working at all and a call back from the customer that panel is broken and the need to give him the password or to come and put back the commissionned values....

Can i say again i don't like this CPU ....i feel better when i say it.

Also i got a 275ms scan time with the same program i usually use with 25 ms on other basic PLC

Twido "zeroes" variables at cold restart or when you download whole program to twido (online edits and warm restart don't return variable values to 0.)

You can hardcode initial values to constant words (%KWx) and move "initial values" when PLC is restarted and %MW variable is zero.
If there is lot of variables, you can use index addressing to this.

Disadvantage for this that when you use constant word to initial values, you can only change these initial values only at offline, and after that you have donload program to PLC.

How long time your plc is off, PLC's internal battery remains values at least one month? (Schneider's documentation)