Host Engineering Forum

General Category => DirectSOFT => Topic started by: bruce on June 11, 2010, 11:56:16 AM

Title: digital s/w filter
Post by: bruce on June 11, 2010, 11:56:16 AM

has anyone worked out code for a filter in a pid loop. i have a lot of noise in my K thermo's coming back to my plc. loops are for high temp glass ovens.

Title: Re: digital s/w filter
Post by: Greg on June 11, 2010, 12:11:28 PM

In DirectSOFT5, there are 2 IBoxes: FILTER and FILTERB.

FILTER: BCD
FILTERB: Binary

Both of these do a 1st-order filter on the specified Raw Data value using the specified time interval.

New = Old + ((Raw - Old)/FDC)

Title: Re: digital s/w filter
Post by: bruce on June 11, 2010, 12:37:53 PM

thanks, i'll look for that and see how it works.
B