This is indeed a specialized control function. You may have to write custom code or have it written in Labview or associated software. Many fermentation control units will make automated acid and base additions to keep cultures at a single pH set point, but these seldom change during a multi hour run (their use rates do change markedly, of course). It may be possible to have the set point change on a set schedule but this would be stepwise. Having a continuously changing pH function (linear or otherwise) might be a challenge in these purposefully simple programs. Would a stepwise control function be suitable?

Dear Edward,

thanks fro your reply.

I guess that stepwise function will be suitable as long as I can get time steps of 5 or 10 minutes.

Anyway, I have no idea of coding... Because of that i was looking for something already in the market that could do the job.

How complicated will be to code or program this thing?

Thanks

Hi Carlos:

You can use a "Cinac" machine:

http://www.amsalliance.com/product/icinac

It does just what you are looking for. pH set point profiles can be easily programmed e.g.:

Control at pH 6.0 from To to 60 min., pH 5.5 from 61 min to 120min, etc.

It logs the pH constantly and it can control inputs like base dosing to maintop pH during a fermentation. It is very flexible, multi-channel and no coding is required. Also not cheap :)

Cheers,