Shucks !! I have LM35....

So what I was thinking. ?

 

Just something to think about if using an LM35. Is it going to be in a hostile enviroment? (Moist hot air). This is probably why they used a sealed temp sensor (the one in the picture for the oven was a hostile enviroment Microwave oven with fan forced heating).

 

Bugger !!!!!!

 

Hi R!f@@. Thermocouples generate a DC voltage when heated. resistance check will read 1-7 ohms aprox.

I don't think that resistance reading is meaningful in general. It is really a function of the voltage your multimeter is using for its resistance measurement function, since the thermocouple will have a fixed voltage drop across it and does not have ohmic behavior

 

It ain't a thermocouple either, i dunno.

Cannot measure any mV when heated.

 

How about I seal a LM35 in a metal cylinder filling it with thermal adhesive.
I have arctic silver thermal adhesive u know.
Will it work ?

 

Well, you might just use some arctic silver on the body of the device, but keep it away from the terminals.

I'd use more than one LM35 - set them some distance from each other. If the readings are quite a bit different between the two, you may have a bad sensor.

 

Ya I need to insulate the terminals. I bet heat shrink tubing will do. The temperature rise will be no more than 170°F.

I'd use more than one LM35 - set them some distance from each other. If the readings are quite a bit different between the two, you may have a bad sensor.

I did not get this part.

 

I was trying to tell you to use two LM35 temp sensors, and monitor both of them. If you only have one temp sensor and it goes bad, you may wind up having the dryer heat up way too much and cause a fire. If you have two sensors, you can compare one reading against the other.

 

Oh tht...no worries. It has a thermal overload cutoff in the mains path.

 

What is better for the job..a LM35 or a NTC.?

Wait..since I am using the original harness, I cannot got for more than two terminal sensors.

 

I suspect the original will be an NTC thermistor as its 2 wire. Thermo couples tend to be for mutch higher temps.

 

Friggin Maldives again..

No thermistors what so ever to sell... Grrrrrrrr.

I like to know which is better this application, from this.
My max temp is around 170°F. Temperature taken from a working one shows no more than 168°F.

 

I am thinking of buying this one.
What do you think?

 

Certainly looks the type that would handle hot moist air from a drier.

 

They look good to me too, but I fail to see why you need ±0.15°C @ 0°C tolerance?
Even class 2B should be adequate; ±0.6°C @ 0°C. That's roughly ±1.1°F @ 32°F.
Why don't you request a quote for both class A and 2B probes?

I have no idea what they'd want for them, but you should probably order several extra in case they need replacement at some point.

 

How about something like this, B57164 thermistor $0.77

http://search.digikey.com/scripts/dksearch/dksus.dll?vendor=0&keywords=b57164

 

I requested a quote....if they do not give me one, I had to find some one in USA who would get it for me.

Chips.
I needed a tough one. I have some of those epoxy types but I do not have any data.
I'll show u what I have soon.

 

Just curious, why not use the original thermistor?

 

Because it is dead and he doesn't know what it is.