Temperature probes vs dial thermometers

I'm designing my HERMS system, and I've been trying to decide whether to use dial thermometers or temperature probes.
My question is...

If I use the temperature probes like those used here, do I have to connect them to a PID like they have? All I'd really like is a digital read-out that I can have on my control panel.

Hi

You can connect them to a *compatible* digital readout. The probe in the link is a 100 ohm RTD. That's different than a 10K ohm NTC or a type K thermistor. As long as the readout is expecting the probe you have, it will read out.

In many cases it's cheaper to buy a readout + sensor than to buy them separately. The gotcha there is that you then need to adapt their cheap sensor to your setup.

Some math:

Cheap sensor + probe, brand new - eBay $6 delivered. Plus stuff to make it like the one in the picture total -> $35.

Sensor like the one in the picture - $25. Plus cheap eBay PID total -> $35 to $40.

Bob

What about these?
http://www.aliexpress.com/store/pro...r-K-Type-Thermocouple-F/508924_500773995.html
http://www.aliexpress.com/store/pro...for-RTD-PT100-Sensors-F/508924_500781120.html

What's the difference between RTD and type K?

lunchbox said:

What about these?
http://www.aliexpress.com/store/pro...r-K-Type-Thermocouple-F/508924_500773995.html
http://www.aliexpress.com/store/pro...for-RTD-PT100-Sensors-F/508924_500781120.html

What's the difference between RTD and type K?

Click to expand...

Hi

The first one is for a K type thermocouple. It will not work with the probe in your original post. The second one appears to work with an RTD. It needs 24 VDC power...

Bob