Andrew Gabriel wrote:
In article ,
"AWM" writes:


A few ways you can do this Picot do printer port data loggers than can be
read directly into Excel spread sheets --- I've tried this and it works.
Howerver a better way of measuring temperature is using Dallals
semiconductor DS18S20 temperature sensor, a selection of software for
reading these is available off the net but you may find a combinatio of
Autom8it and Quasar electroics 3145 temperature logger the easiest and
cheapest to get working.
Links
http://www.picotech.com/data.html
http://autom8it.com/
http://quasarelectronics.com/computer_projects.htm


Another link: http://www.phanderson.com

I am using one of Phil's modules to read 3 DS18S20's (upstairs,
downstairs, outdoors) and two analogue inputs (upstairs and
downstairs potentiometers as room stats) to control a two zone
heating system. I have been thinking of attaching DS18S20's to
the flow and return, although the Dallas datasheet says they
may not work well in parasitic mode at high temperatures due
to increased current leakage inside the devices, and Phil's
module does drive them in parasitic mode (multiple devices on
a single cable pair).


Depends how much the error is, if its a lot it is back to an adc and
thermistor(s) which would need calibrated, it would be good to collect
boiler exhaust gas temperature also by sticking a thermo couple into it.


Phil's module provides the data over an RS232 serial link, which
I access with a purpose designed program (which I'm still working
on). In Windows, you would probably need to write a program to
interface between the serial port data and Excel.