Temperature Controller

If the controller is setup for both types of temp probes, then yes a thermocouple can be used instead of an rtd. The controller will need to be reset for the new temp probe. Just use the correct type thermocouple and wire the controller is setup with. example: type k, type j, type t,... Thermocouple color codes/types.

Just check the manual of the controller or lookup the info online. Just get the Make, model, serial number.

sir, does all pid controller comes with the setup for both type of temp probes?

No. Not necessarily.

sir ,

What is the physical difference b/w thermocouple & rtd , i mean how can one know that the given sensor is either thermocouple or rtd only by seeing that.

Thanks

When either the Thermocuple or the RTD are bare , it is easy to know which is one .

A termocuple is a pair of twisted , or not , isolated wires , and at the end it are solder by self fusion.

Usually one wire is magnetigc the other not , it depend of the thermocuple type.

See here

https://www.google.com.ar/search?q=thermocouple&hl=es-419&prmd=imvns&source=lnms&tbm=isch&sa=X&ei=JEgfUNnKOIje0gGC-YDgBQ&sqi=2&ved=0CFUQ_AUoAQ&biw=1280&bih=653

A RTD , is a small square , about 2 to 4 mm side .

http://www.google.com.ar/imgres?hl=es-419&biw=1280&bih=653&tbm=isch&tbnid=hYVfEVfex2hLIM:&imgrefurl=http://spanish.alibaba.com/product-gs/platinum-rtd-pt100-elements-4-1x4-2mm-513230765.html&docid=RG0UVl4VxFTLeM&itg=1&imgurl=http://img.alibaba.com/photo/513230765/Platinum_RTD_PT100_Elements_4_1x4_2mm.jpg&w=500&h=500&ei=ZUgfUGWmgdEBp66A0Aw&zoom=1&iact=hc&vpx=399&vpy=252&dur=4235&hovh=225&hovw=225&tx=108&ty=62&sig=105802027003060146058&page=3&tbnh=149&tbnw=160&start=44&ndsp=25&ved=1t:429,r:13,s:44,i:250

also

https://www.google.com.ar/search?q=thermocouple&hl=es-419&prmd=imvns&source=lnms&tbm=isch&sa=X&ei=JEgfUNnKOIje0gGC-YDgBQ&sqi=2&ved=0CFUQ_AUoAQ&biw=1280&bih=653#hl=es-419&tbm=isch&sa=1&q=rtd+pt100&oq=rtd+pt100&gs_l=img.12...0.0.2.71414.0.0.0.0.0.0.0.0..0.0...0.0...1c.PmOH8yRwClE&pbx=1&bav=on.2,or.r_gc.r_pw.r_cp.r_qf.&fp=da6b0ce3aab3e271&biw=1280&bih=653

At last ,

Thermocouples bear tension when temperature change, or mVolts

RTD change resistance or OHMS

What the make and model number of the controller your wanting to use?

Might be able to get the info online for you.

To all: Keep in mind that replacing an RTD with a thermocouple (even when the electronics are available and/or already setup) will not likely give you the same controlled results. RTD's are precision temperature measuring devices (general accuracy of +/- 0.2 degF) whereas thermocouples, unless calibrated provide fairly coarse measurements (Type K has accuracy of +/- 4 degF).

Replacing an in service RTD with a thermocouple would be an unusual way to improve the process.

Replacing an in service thermocouple with an RTD is an acceptable way to improve temperature control, not the other way around.

From what I've seen of commercial devices they're typically only meant for thermocouples or RTD use not both.

Ask the particular manufacturer. He will guide you.

In following this thread, it does not appear that you are well qualified for this type of work. Knowing the difference between a thermocouple and an RTD is pretty basic information. If this is not within your toolkit of knowledge, then setting up of the equipment, commissioning it, tuning and troubleshooting will be well beyond your scope of experience.

You and your company will be well served by getting an engineer or technician who is knowledgeable and experienced with electronics to do this work for you.