At 06:20 AM 1/29/2009, you wrote:
>From: "Andre Abelian" <aabelian@mason-electric.com>
>
>Why do you need to put temperature sensor in concrete ?
>I am just cereus? Suppose you know the temperature ? then
>What are going to do with it?
>
>Thanks
>
>Andre

The purpose is to measure different heating zones of a solar powered 
radiant floor heating system
for a single family home. Area of concrete approx 4200sqft. The 
temperature readings are used
to adjust the hot water flow through the different zones and to monitor the
performance of the overall system in general (there will also be 
temperature sensors
to monitor ground temperature  (below concrete - to verify 
effectiveness of insulation
of concrete floor to underlying ground essentially), water 
temperature in the entry and return loops
and outside air temperature, as water temperature also needs to be a 
function of the
temperature delta between outside and inside temperatures.

So for the concrete based sensors you are looking probably at 
something like 20 sensors
with cable runs of up to 200 ft to get to the central collecting point.


best regards
Volker
MicroController Pros Corporation
microcontrollershop.com
The World's Largest Embedded Tool Selection
+1-408-776-7992 Phone
+1-215-243-6071 Fax  
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