So you see, software is not all about zeroes and ones, on and off. As soon as it interfaces to the real world you have to work with 'almost on', and 'nearly one'. Using sensitive analogue circuits like the LM35 near large electrical devices like motors and heaters is always tricky. Actually I think it would be better to use a digital output temperature sensor (I think Dallas makes them) That would free you from long line interference. And of course the best would be to use real industrial type temperature sensors with a 4-20mA (or Hart) interface.

Cees Meijer Software / Hardware Engineer Qmetrix BV C-Scope Blog C-Scope Website

That's why you ALWAYS, ALWAYS should enclose the statement (even a single one) in braces. Even if omit them because you're 100% sure that only one statement is required in the if() or else body, it will bite you somewhere in the future (Sure, 100%...)

Cees Meijer Software / Hardware Engineer QMetrix BV Specialists in River and Sea flow measurements.

Hmm. I know you all use Visual C. Though I seldom make this mistake, Borlands C++Builder compiler gives me a neat warning: 'Possibly incorrect statement.:cool:'

Cees Meijer Software / Hardware Engineer QMetrix BV Specialists in River and Sea flow measurements.