Recommended Posts

My head has spun numerous times from reading through your thorough explanations/recommendations regarding humidification systems.  While I am a highly educated man, I wish I could grasp all the intricacies you speak of so knowingly.  I also wish I had the talent to take on a self-build humidor.  Alas, I do not and can accept this.

One thing I can understand:  That is remarkably consistent performance.  Congrats!

  • Like 1
Link to post
Share on other sites

Thanks for this chart PigFish!  It's nice and comforting to see that change in RH% over a daily period - as the delta matches quite well with what I am seeing in my wineador.  I too see a variation of 2-3% over the course of the day if there are big tempurature swings between day and night - which is quite common here in Lithgow for this time of year.

Unless of course i am reading that chart all wrong - possible - I am certainly no expert!

Link to post
Share on other sites

Actually I think I am reading that chart wrong - that variation in RH on the chart is showing at better than 1 minute resolution, so would I be right in saying that the 3% or so variation I see in the chart is just the result of PID set point over/under-shoot?  I take it you are using active humidification - I am surprised to see this time resolution of change in RH - I always thought RH would be more sluggish to change.  If so, this consistency is remarkable!  Well done!

Link to post
Share on other sites

I too find the rH zig zag interesting.  The cycle is so rapid though that I'll bet a reading inside a cigar box, or even inside one of the cigars, would be as flat as the temperature reading.  I believe you've said before that rapid, tiny cycles is what you're after.  What is theoretically possible in shrinking that range of 58-62 rH?

Link to post
Share on other sites
14 hours ago, IanMcLean68 said:

Actually I think I am reading that chart wrong - that variation in RH on the chart is showing at better than 1 minute resolution, so would I be right in saying that the 3% or so variation I see in the chart is just the result of PID set point over/under-shoot?  I take it you are using active humidification - I am surprised to see this time resolution of change in RH - I always thought RH would be more sluggish to change.  If so, this consistency is remarkable!  Well done!

Yep, you got it. There actually is no comparison in performance between a "standard" wineador and Piggy's set-up (almost apples and oranges). With active cooling, there has to be a cycling - that's inevitable. But restricting amplitudes and time constants (response time) to a minimum is what it's all about. That makes for stability and for a quick and effective response to disturbances (like a 5-min door opening, while you are Tetris-ing...). The observed variation is not strictly an "overshoot", as you say, since a certain delta is always needed to effect regulation. Finding the optimum between amplitude and duration, i.e. effective periods, makes the "artistry". Here, from what we see in the graph, there is effectively neither to spot any short-term nor diurnal variation in rH and temp. That climate-chamber of Piggert is rocksteady.

To briefly address rH - that can very well change rapidly, why should it not? A change in temp. will always induce an instant rH change - already without a major actual change in aH. Time constants of both, T and rH, will usually match closely. Since temperature can change rapidly, so will do rH - which is also why you need utmost stability when doing instrument calibration. Active humidification and dehumidification (condensation) processes should also ideally display an instant response. A slow change in a humidor often just indicates poor circulation and mixing (and perhaps also slow-response sensors...) - and that will then be prone to producing overshoot reactions.

People often don't recognize the importance of the effect of time constants. Having a proper understanding of what that means to the products in storage is crucial. For example, a diurnal, i.e. one-time 3% rH change during a 24-h cycle is rather bad, since cigars, in particular when stored open like in single drawers, will have time to react to that. Thus will repeatedly "work", gain and lose part of their humidity within a comparatively short period of time. The same 3%-variation over a 5-min-cycle (the shorter, the better) will be harmless, as the tobacco won't actually be able to follow and adapt to such a short-term variation (even less so when in boxes). On the other hand, a slow and steady 3% long-term change during the course of the year, again is uncritical, as cigars have time to react and adapt slowly, and are not constantly "working". The outcome of that again would be an - alternative - form of long-term "stability". So, it is important to always consider the temporal course of variations in environmental parameters and not just their amplitudes.

Link to post
Share on other sites
On 3/15/2017 at 6:50 AM, Fugu said:

People often don't recognize the importance of the effect of time constants. Having a proper understanding of what that means to the products in storage is crucial. For example, a diurnal, i.e. one-time 3% rH change during a 24-h cycle is rather bad, since cigars, in particular when stored open like in single drawers, will have time to react to that. Thus will repeatedly "work", gain and lose part of their humidity within a comparatively short period of time. The same 3%-variation over a 5-min-cycle (the shorter, the better) will be harmless, as the tobacco won't actually be able to follow and adapt to such a short-term variation (even less so when in boxes). On the other hand, a slow and steady 3% long-term change during the course of the year, again is uncritical, as cigars have time to react and adapt slowly, and are not constantly "working". The outcome of that again would be an - alternative - form of long-term "stability". So, it is important to always consider the temporal course of variations in environmental parameters and not just their amplitudes.

Very interesting, I've never thought about this.

Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
  • Recently Browsing   0 members

    No registered users viewing this page.

Community Software by Invision Power Services, Inc.