Need help in resolving a Controller-ramp function

[RENN]

i use 2 valves named valve 1 and valve2.      Both outputs vary between 0-100%. i would like to control the output of valve2 with a +ve and -ve ramp.

when i have valve1 with an output less than 20%, i open the valve2 till the valve 1 is closed upto 50% (i use an independent PID for valve 1). and if valve1 opens above 80%, i close valve2  till the valve1 reaches 50%.

i need to use 60 seconds to valve2max and 60 output increments to control valve2.

now i'm trying to work with the +ve ramp.

please give your valuable suggestions and please correct me in making my LabVIEW code better...

[RENN]

i have problems with using the exact 60 output increments.

[tinnitus]

hello Renn,

first of all , before coding anything else, dot not use staked sequence any more, it's unscalable

have a look on event structure and state machine, with search function and with labview templates. 

ps: i'm looking for links and i'll repost

Best regards

Tinnitus

http://zone.ni.com/devzone/cda/tut/p/id/3024

Message Edité par tinnitus le 02-01-2009 12:12 PM

[tinnitus]

http://zone.ni.com/devzone/cda/tut/p/id/7466

[RENN]

Hello Tinnitus,

thanks so much for your reply.

could you please  send the link again? the url "http://zone.ni.com/devzone/cda/tut/p/id/3024" is not valid

Renn

[tinnitus]

sorry its appends , i don't know why,

try to make a copy-past in url

tell if it work by this way

[tinnitus]

sorry its appends , i don't know why,

try to make a copy-past in url

tell if it work by this way

there is two links: one ending with 7466 other with 3024

Message Edité par tinnitus le 02-01-2009 12:25 PM

[RENN]

Hi Tinnitus,

as you suggested, i tried a statemaschine version of the same requirements. i feel it more compact.

but still i have a problem with the ramp - i mean the increment of Valve 2 output.

please have a look at the attached  Vi. i am not getting a possible solution to better increment the V2 output

V1max=V2max=100.

time to increment V2 from 0-100 is 60 seconds

thanks

Renn

[RENN]

i think the while loop execution rate is a bit higher to make the remainder output in case "+ve ramp V2" equal to zero

[tinnitus]

Message Edité par tinnitus le 02-01-2009 02:24 PM