Answer / king

Rtd is used for low range temperatures based on resustance (ohm law) where as thermocouple used to measure high range temperatures.

Answer / manikandn

tc and rtd using temperature measurement. but rtd is high accuracy characteristics ,but low temperature measurement.thermocouple is high temperature measurement.

Answer / b v s rayudu

RTD works on PTC and exhibits linear characteristics in some region. Platinum material is mostly used, response is slower, high accurate and signal conditioning techniques are bit easier. For RTDs separate excitation required.

Thermo couples (TC) works on Seebeck effect, exhibits exponential characteristics, faster response, cold junction compensation is the disadvantage, separate excitation not required, output signal level is very low.

Answer / dhaval

we also use tc in low range. but main prps high tamreture tc value constant cmpare to rtd and rtd we use in high temprreture that time ohms drop so ..

Answer / mohammad ehtesham khan

TC is a High temperature Sensing element, which is used to measure high temperature and
TC works on the principle of Seebeck effect, the out of TC is MV. TC made by different metal.
RTD is low temperature sensing element, which is used to measure low temperature, RTD works on Ohms law principle, the out put of RTD is ohms

Answer / kshitij parashar

Rtd is conductor type sensor & Thermocouple is semiconductor type sensor.All conductor sensor is used for high temperature measurement and all semiconductor sensor is used for low temperature measurement as per principal for temperature sensing.

Please send the all question with answer related for interview.

1 Answers  

1. How many output signals do wew have in process control? 2. Could you write down the names of the pre-commissioning and commissioning stage test instruments and explain them (more than 5 items)? 3. What is the first step to commission a transmitter on service? 4. What is RTD? 5. Find the output value in MA of a temperature transmitter (RTD Type) at 120degree celius? 6. What is the O/P signal of a pneumatic transmitter? 7. What is the O/P signal of an elctronic transmitter? 8. What is the close loop and open loon?

4 Answers  

what is bevel? why bevel required in orifice plate?

2 Answers  

what is difference between RTD , thermo couple and thermistor in general ?? (except temperature co-efficient )

5 Answers   Bilt,

Any Transmitter Range (Span value) start from 2?

1 Answers   Exxon Mobil,

what is absolute pressure, gauge pressure and atmospheric pressure?

2 Answers   Mother Dairy,

With N nodes and B branches what will have a network ???

0 Answers   BSNL,

I want to take temp. data from recorder to computer. Which communication system is best from this option(Rs 232- 485/ethernet/USB)?

3 Answers  

what is beta ratio?

3 Answers  

how to measure oxygen which methods are using?

0 Answers  

Can we place a Control Panel in Hazardous area Group IIC ? If 'yes' then is there any approval required? If 'yes' then there is any specific IP rating or any standard required? If 'Yes' What is MOC of control panel?

2 Answers  

What is the use of temprature compensation?

0 Answers