Meta data source, alarm triggering, execution delay

[skiv71]

hi, i set a meta data tag which calculates hi alarm points based on room sp+hi offset and then compares this to actual temp.

works great, but i really wanna purge/blip the condition output... i.e. sustained overtemp of 15s causes output...

i can do this at the alarm trigger fine... but i really want to purge/blip the trigger meta data source output tag because it shows a hi temp color flip image on the screen and when the temp flicks around the trigger level, it looks spurious.

i tried the execution delay, but with anything but 0, the script wouldn't function

thanks

skiv

[mlohbihler]

purge/blip?

Have you read the meta point documentation?

[skiv71]

hi yea i have read it and managed to get as far as i have...

just bit unclear regarding the execution delay...

basically... i have 4 variables..

temp (temp)
setpoint (sp)
hi offset (hi)
lo offset (lo)

then.... my script...

if (temp.value>=sp.value+hi.value) value=1;
else if (temp.value<=sp.value+lo.value) value=-1;
else value=0;
return value;

and the register output maps to a analog image.

even if the temp does go out the limits (set from the maths), i want to have the condition sustained for x period before setting the "1" or "-1"

to avoid spurious temperature fluctuations.

thought execution delay might have been it, but suspect i may need to do this another way..?

[mlohbihler]

A point is a point. It's value is the result of the calculation. I think what you're after is event detection. You can create a point event detector on the meta point that say "if state=1 for at least 5 minutes", or whatever you want.

If you definitely want this in a point value, you can have an event handler on the detector that sets the value of a point on active and inactive events. You could then have two binary points that represent high and low limit active/inactive.