Dataloggers

Gregory Basso <greg.basso [at] verizon__net> writes

>Another concern would sensor range. Having over 12 years of
>experience with wireless telemetry, I would question the range of a
>small battery powered sensor with a stated battery life of 5-10
>years. ...

Obviously we all tend to work with systems we know and like and so
direct comparisons are hard to make. However, I tend to work in
medieval buildings with very thick and often damp walls, but also
with 19th century structures with metal reinforced construction--so
fairly demanding from the transmission point of view. My experience
is that Eltek system works pretty well. Larger distance or more
complex structures can be tackled with repeaters. Bandwidth would be
a consideration with a very large system, but the ability to set
multiple transmission intervals per log seems to reduce possible
data loss to a negligible amount. The only problem I have found is
in the occasional enclosed reinforced basement (or similar
situation) with a lot of electrical activity, which can defeat
pretty much all systems. If this is an essential area, you can run
in a hard wired probe, or use an extended antenna outside the area.
I suppose this sort of situation is the trade off between the
convenience of hard wired and telemetric systems.

I understand the that the systems are available in the US.

Tobit Curteis
Tobit Curteis Associates
36 Abbey Road
Cambridge
CB5 8HQ
UK
+44 1223 501958
Fax: +44 1223 304190


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                  Conservation DistList Instance 19:27
               Distributed: Wednesday, November 23, 2005
                       Message Id: cdl-19-27-002
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