Helen
The voices calling out for mechanical solutions to poor environmental
conditions in display cabinets are not only very challenging, but also
very persistent. I have been working in microclimate control, mostly to
provide appropriate humidities for museum display, for more than twenty
years now, and no matter how many times I explain the difficulty and
challenges of combining humidity and temperature control, inquiries for
showcase cooling devices keep coming in.
It is important to bear in mind that the purpose of providing a humidity
control system in a showcase is to compensate for changes in humidity
brought on by temperature changes. Unless the object on display has a
particularly sensitive reaction to temperature variations, temperature
control is likely not needed for most artefacts on display. It is the
need for stable humidities that has driven the development of products
like Prosorb buffering compound, or Preservatech's microclimate
generators. It is rare that temperature control is truly needed.
Passive humidity control (Prosorb, silica gel) works effectively on
smaller, well sealed showcases, and prevents damage from major humidity
fluctuations. Active humidity control devices are common and relatively
easy to provide, requiring little power, and allow the use of existing
older or less than perfectly sealed showcases.
Temperature control takes much more sophisticated machinery and control
systems when compared to humidity control, but can be done. Power, noise
control, ambient conditions, and other demands begin to enter the
picture, as well as bespoke showcases - obviously expenses will be greater.
Until very recently, all temperature control systems for showcases were
unique assemblies of machinery and control systems. My own experience
goes back to the mid-nineties, and the time and effortinvolved in
achieving a reliable solution were seldom the investment of my time. My
partners and I have worked with all manner of devices and dispositions
as we explored possible solutions. However, although a poor business
investment, we continued to take on the occasional showcase cooling
project, and learned with every challenge accepted. We can now offer
mechanical control of both temperature and humidity for most showcases.
There are, of course, caveats. The most important being early
involvement of client, showcase builder, and machinery provider. This is
a complex topic, and there are many questions to be answered before a
more complete estimate of your needs can be determined. Please inquire
off-list and I can likely assist you.
js
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Jerry Shiner
Keepsafe Microclimate Systems www.keepsafe.ca
+1 416 703 4696 i...@keepsafe.ca Skype: jerry.shiner
Specializing in the design, procurement, and installation of environmental
control systems for museum and archives
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