Lack of Reliable Power

[PapaDisco]

I want to add a wineador to my Saigon office.  It's too difficult to do any sophisticated mods over there so I have to work with something stock.  

I was thinking I'd just buy a stock wine cooler, leave the drain open, and then store each box (or two or three) in a freezer ziplock with a 65% or 70% Boveda.

Here's the problem: electrical power is still unreliable in Ho Chi Minh City and every week you get at least one outage that can last from 10 minutes to an hour or two.  The 10 minute outage is no problem, but in 15 minutes your office space can quickly go to 85-90F.  

Getting the best insulated wine cooler I can find is a first defense, but after that, I need to find a way to deal with cigars in ziplocks that are cycling up to 90F and then quickly back down to 65F.  It's the "quickly" part that's the problem.  If this cycle happens in the middle of the night I can't be there to turn the thing on and off, or open the ziplocks to minimize condensation from the cooling air.

Any ideas?  

[PigFish]

This is not really my expertise but I will take a shot at it.

I can likely take one of my controllers and with the use of two NTC or thermocouple sensors make a comparison of the two sensors at start-up. I am not positive that I can pull this off but I think I can...

What the system would do is look at sensor 2 at power on and compare it to sensor 1 used to run the system. Both sensors would have to be in the cooler. Why? Well, what happens if the power goes on and off quickly verses over the course of hours? You don't want to start an 'event' based on the worst scenario, you want to mark it, and set the datum at a temperature that the system needs to 'recover' from, then soft start the system moving the set point a matter of X degrees (C or F) per minutes of time.

Let say we set up the algorithm at 0.5F/ 10 minutes. AGAIN, ASSUMING THAT IT CAN BE DONE THIS WAY. At start up the controller looks at sensor 1 and 2 and compares them. It calculates the delta between the desired set point, say 70F and the two sensors. If the controller finds that the sensors read 74 then it knows that it needs to move 4F to get back to 70 and that it needs to start at 74F... I know it sounds like it should be done with one sensor, but you have to take into account that the controller really should be looking at the ambient in this case... If you trick it and call the ambient the temperature of the interior, it will bend the algorithm to meet the need of your outage and not the ambient. I see this as the smart way to do it...

So in this case it starts at 74 with a goal of 70F. It runs the system at start to 73.5 as the temporary set point. It gets it there and holds it for 600 seconds. Then it moves the temp set point to 73 and holds it for 600 seconds and resets the temp set point again to 72.5 and so on...

If you are using a compressor cooler we set the time to restart the compressor to say 4 minutes. This protects the compressor for short cycle...

This is theory of course and I would not know that I can do it until I research it. I don't have time to research it today on a whim... but that is my input on the matter!

This is at least one way to skin the cat if you have this problem. That is, without a more sophisticated PLC and a lot of programming!

Cheers! -Ray

[PapaDisco]

I've got nothin' for tools in Saigon though.  No drill, nothing.  I suppose it would be possible to just run the sensor wires (if they're thin enough) through the door seal . . .

But that said, being able to program the controller so that it only moved the temp slowly, so that the Bovedas could keep up, would be ideal. 

If one knew how slow a Boveda worked and at what temperature, I suppose it would be possible to estimate the likelihood of condensate forming during the cooling cycle.  Minimizing air in the Ziplocks might help?  Or would that just be giving the water no where to go during the heating cycle?

[PapaDisco]

What about a simple timer?  Triggered by a temperature increase of X degrees, it then turns on power to the compressor for Y minutes every period.  The length of run time and frequency would be determined by how fast a Boveda absorbs.  If one knows the cooling capacity of one's unit, you might be able to approximate this to some useful level of functionality.

Not quite up to Piggie's standard for finesse, but perhaps workable for the jungle??  

[Fuzz]

What about plugging the wineador into a UPS?

[PapaDisco]

2 hours ago, Fuzz said:

What about plugging the wineador into a UPS?

Would one of those have enough gumption to run a compressor?  Seems like a lot to ask of a wee UPS? 

[PigFish]

12 hours ago, PapaDisco said:

What about a simple timer?  Triggered by a temperature increase of X degrees, it then turns on power to the compressor for Y minutes every period.  The length of run time and frequency would be determined by how fast a Boveda absorbs.  If one knows the cooling capacity of one's unit, you might be able to approximate this to some useful level of functionality.

Not quite up to Piggie's standard for finesse, but perhaps workable for the jungle??  

...anything is possible, knowing your platform and how it will behave.

Today I am running two series logic controllers to run Gen 13 humidors. While this is not about what 'I am doing' I bring it up as an example.

Looking at secondary controller logic, you have two choices. One would be to evaluate the condition of the humidor in parallel with the primary controller, and two would be to use simpler logic functions and timers. Both strategies can work, both are actually quite complex... but the fact is, examination of sensor data is 'typically' superior.

The fact remains, that timer functions, while extremely useful, are not competent enough to judge complex changes in humidor conditions. A timer has no means of logic beyond a set time and calculations based on other timers. More complex timer functions (ones that I use) can measure time parameters and make calculations. The key is, you need to know your system in order to start with timed logic functions or you are just guessing.

I could build either of these systems, I can make something that will likely work for you... But I am not you, I am not in Saigon, with my tools... I would assume that 'ones' budget does not include flying me there!!! -LOL

A sensor based solution is the likely the only one that will work here. If that is not the case, then the next would in fact be, buying enough UPS power to take you through the worst of conditions. Frankly, that is the easiest solution and the one best for the cigars themselves.

The fact is, the hysteresis on your Boveda packs are not likely that good in the first place. A large part of this depends on the total surface area of the Boveda and the cubic feet of storage that you have.

Bovedas are likely the worst possible humidification system here. While the are bidirectional, they are (theoretically) constant delivery systems. I believe a high density bead product, or even a combination of the two might be the best. Desiccants behave more like the cigars themselves, so they will tend to work along side the cigars rather than compete with them. As your system warms they will both give off water and the beads will therefore supplement the cigars when needed. As the system cools they both take on water, thus taking up the free water and not allowing all that water to reenter the cigar. I think beads are better here! As your system heats, the Bovedas (in theory) allow your cigars to go dry... The water lost from the cigar will end up as condensation on the cooling coil when the system returns to power. You will end up with wild runs of wet and dry in the humidor as a result...

Furthermore beads have a large surface area. They are not fast acting, not by my controlled standard, but they are likely much faster than the Boveda product.

As I stray here, you should remember that I am constantly viewing any humidor as a 'fully working' humidor. It is simply the datum from which I operate.

Best of luck mate! -R

[Fuzz]

18 hours ago, PapaDisco said:

Would one of those have enough gumption to run a compressor?  Seems like a lot to ask of a wee UPS? 

Depends on the UPS. Of course you won't be using a dinky little $100-$200 UPS that you use for your computer. You can get 2000-3000VA rated UPS for medical fridges. Cost may be a bit high, though ($1000+).

[PapaDisco]

2 hours ago, Fuzz said:

Depends on the UPS. Of course you won't be using a dinky little $100-$200 UPS that you use for your computer. You can get 2000-3000VA rated UPS for medical fridges. Cost may be a bit high, though ($1000+).

Thanks Fuzz.  Would you mind ball parking this for me?  If the wine cooler I'm looking at says 115V, 1.8A, 130W, how do I translate that into UPS requirements?  a 2200VA UPS from APC is $769, so a bit expensive but not out of the question.  How long would something like that provide power to just the fridge?  The only formula I remember is V x A = W  

[Fuzz]

The amperage on the plate should be the amps required when running the compressor. A 1500-2000VA UPS should be more than enough to power a 130W wine cooler for at least an hour.

[PigFish]

5 hours ago, Fuzz said:

The amperage on the plate should be the amps required when running the compressor. A 1500-2000VA UPS should be more than enough to power a 130W wine cooler for at least an hour.

It should be more than that... Remember battery back up systems are generally designed to power an operating resistive load. Compressors are notoriously hard to start. This is why they build tiered starting systems, compression release systems... etc.

Your system my need repeated starts. Your battery may need to deal with surge amps from an inductive source. You would want a system built for, or with the ability to start a small compressor. -R

[Fuzz]

3 hours ago, PigFish said:

It should be more than that... Remember battery back up systems are generally designed to power an operating resistive load. Compressors are notoriously hard to start. This is why they build tiered starting systems, compression release systems... etc.

Your system my need repeated starts. Your battery may need to deal with surge amps from an inductive source. You would want a system built for, or with the ability to start a small compressor. -R

True, the start up amperage is going to be far higher than the running amperage, that's why you go for a much higher spec UPS. I have seen medical fridges (for vaccines and perishable medicines) run on a UPS. The UPS used are pure sinewave versions with ratings in the 2KVA-3KVA 7-9aH range. That kind of UPS is designed to power a medical fridge that keep temps around 2C-8C, including starting up the compressor. The LRA (locked rotor amps) for a compressor is usually 6x the running power, so even if you go higher at 10x, a 3KVA 7-9aH UPS should handle a wine cooler.

[PapaDisco]

Thanks guys.  I'll look for 2000+VA on the UPS and keep my watts under 130.

Magste: I'm not worried about LT aging over here.  The boxes I take to Saigon to hang around long.  I'm mostly concerned with a cigar warming from 65F to 85F and the amount of moisture that would put into the surrounding air.  When the electricity comes back and the chiller kicks on, going from 85F back to 65F quickly will likely generate condensation (and therefore mould).