Can you tell me how we will select RTD and Thermocouples for
Temperature applications. I.e How we will choose accurate
one for a specefic operation if both having same ranges
Answers were Sorted based on User's Feedback
Answer / kumar_abit
Both thermocouples and RTD have their specific advantages,
according to our need we have to choose for our purpose.i am
explaining below:
1.thermocouples can measure up to a temp. of 1700 degree
celcius,where as RTDs are limited to 800 degree celcius
2.Grounded Thermocouples are inheritantly tip sensitive;
while RTD elements are isolated from their sheaths. A
grounded Thermocouple will respond to a 63% step change in
temperature nearly 3 times faster than a RTD counterpart.
3.Normally rtds are costlier i.e.2.5 or 3 times than
thermocouples
4.as the case is taken onbehalf of accuracy and linearity
RTD shows improve characteristics than thermocouple.
5.Due to their linearity and virtually drift free output,
RTDs are more stable than Thermocouples.
Is This Answer Correct ? | 10 Yes | 1 No |
Answer / mazhar ali
both rtd and thermocouple ranges cant b the same , but u can
say that rtd range & thermocouple range may overlap.
if in a process u need to measure a temp of 150 degrees,then
u can use both rtd of 0-300 degrees and thermocouple
0-1200degrees, but u know rtd would be cheaper,money saying
than thermocouple.
for example when u drive a bike the speedometer may be
showing 185kmph, so the gauge of 0-220kmph is better than
using 0-1000kmph, when your bike speed is max 200kmph.
Is This Answer Correct ? | 6 Yes | 7 No |
Answer / kul bhushan emecon controls
Ya i am agree with 2one but the the measure difference
between RTD & Thermocouple on their working principle.
1)RTD is limited up 500-700 degree celcius it is
manufactured up to 1000 degree celcius on special cases.
2)It is mainly used for measurement up to 500 degree
celcius.
3)It is available in 2,3 or 4 wire configuration.
4)We can use transmitter or card when we are interfacing
the RTD with DCS.
5)It's accuracy is good in comparision of Thermocouple on
small Temperature ranges.
Thermocouple
1)It is based on seeback effect.
2)It is generaly use for higher Temperature ranges up to
3000 degree celcui(ceramic type thermocouple in special
case)
3)It is not a 3,4 wire device.
4)Grounded thermocouples are used where fast response is
required.(Thermocouple tip is welded with thermowell.
5)O/P is mV.
Is This Answer Correct ? | 0 Yes | 1 No |
What are the logic behind 2x2 and 2x3 logic and more when ask in interviews
i install a DP transmitter of Faugi on drum level of boiler but i face a problem in it when i engergize the transmitter the meter shows 0 or 100% no variation in it.the distance of two points is 19.5 inches, i am in trouble please suggest me what can i do it's very urgent Please reply me as soon as possible Best regards ikraam haider
Can combine control system for Emergency control system (ESD)and Fire & Gas System ( F & G) is possble to built and offer to client? Can such system is as per Norms in India?
what is skin thermocouple?
I have a Control VAlve having size of 2 ".Only the known parameter is Pressure drop . Its 2 Kg. Then How to calculate control valve sizing means Cv.
how we calculate error in percentage when instrument calibrat
What is the use of temperature compensation?
what are the sensor types of vibration&speed?n what is proximity sensor?
hello this is dhinakar i am completed my instrumentation engg . recently i got job in sugar industry side. i like to ask one question can any one say what are the things i have to follow know more about industrial instrumentation,,,,,,,
define SIMULATION a and what is the need of it
how 3 out of 2 Logic/interlocks works? give brief explanation with help of diagram.
How to find out turn down ratio of Pressure transmitter?