--- alan smith wrote: > Decided not to hijack the threads...start a new one. > > So this new client of mine, dealing with RTD's....are they just so > much more accurate than any other type of temp sensors? He wants to > read once a minute. Then make sure it didnt hit a threshold, and if > it does, turn on an alarm. Its not a temperature controlled process > or anything like that, just simply making sure its staying within > limits. Industry standard is to use RTD's but I'm just curious if > there isnt anything just "as good" ? > RTD sensors are very linear over a large range they are also very accurate. Typically it's -100C to 1200C operating with a 0.010C accuracy. They are a bit more expensive however with 4-5 significant digit accuracy they tend to stay the course better. Also the electronics to acquire a temperature from the device tends to be simpler (it's a bridge). Each sensor has it's strong points. TC's are CHEAP VERY VERY cheap. You can make one with a wielder and some wire. Thermistors are good for low temperatures (IE cryogenics). TC's also can go up into the very high temperature range (exotic TC's but they are cheaper than an RTD). It really depends on what tolerances you have and what application you are using the device in. Also what you are familiar with. ____________________________________________________________________________________ Be a better friend, newshound, and know-it-all with Yahoo! Mobile. Try it now. http://mobile.yahoo.com/;_ylt=Ahu06i62sR8HDtDypao8Wcj9tAcJ -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist