# Classic PID settings



## gingerneil (Aug 21, 2014)

Just a quickie... I'm in the process of taking delivery of various bits to fit a Rex c100 pid. Just wondering what you good folks set as your brew temp and alarm temps for the steam setting?


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## Jim bean (Aug 16, 2014)

Hi gingerneil I hover between 101c or 102c for brew I guesstimated at this through tasting but checked it with a thermofilter recently and is around 93/94c so 8/9c off set yours might be different though so set at 100c taste ten 99c then 101c work from there

150c for steam the instructions for setting the alarm are vague at best but if you enter these settings the alarm should work then you can play around with AL1 setting to get your best steam temp

AL1 0048 (+ SV 0102c =alarm1 comes on @ 0150c)

SL7 0001

AH1 0001

Cheers James


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## gingerneil (Aug 21, 2014)

Thanks. And thanks to for all your hard work on fitting a DIY pid. You've cropped up on just about every forum I've searched!

There seems to be different ways of setting the alarm, and the online of guides aren't clear. Some say to set the absolute value, others say set it as a difference to the standard temp... Are you confident that the Rex c100 is set as a difference?


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## MrShades (Jul 29, 2009)

Yes it is set as difference, Jim's details are pretty good.

SL4 0001 (deviation high alarm)

SL7 0001 (changes the alarm operation from NC to NO - so that when the temp increases to SV+AL1 the alarm triggers and turns the heat OFF)

AL1 0040 (or something like 40... exact number is art rather than science. Should get good steam with any value from about 30 upwards, but don't go too high. 50 is probably cooking it a bit too much...

AH1 0001 (alarm differential gap - how far away from the Alarm point does temp need to drift before alarm goes on/off - so this is 1C.)

Note that if you have a Pt100 then some of these settings have an implicit decimal place... so AL1 at 0040 becomes AL1 040.0 and AH1 is 001.0 (mine are set to 0030.0 and 000.2)


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## gingerneil (Aug 21, 2014)

Thanks MrShades. As for the pt100, I'm hoping a certain forum member might help out!


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## MrShades (Jul 29, 2009)

Yeah, working on it ;-)


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## redzocco (Mar 22, 2021)

I'm about to pull the trigger on a Classic PID and this thread is really helpful, thank you 🙌🏻


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