Answer / balajirajgopal

i assume u asked for thermocouple .as per seeback effect 2
junctions of the thermocouple should be maintained at
different temperature i.e. hot junction in high temp and
cold jn at zero degree temp.but in practical application it
is difficult to maintain cold jn at 0deg C .so a thermister
is placed in the location where the cold jn. is kept.the o/p
of thermister is used to measure the temp at that location
and is used in calculation to neglect the the effect of temp
at cold jn.

pls dont ask me the calculation,bcause i am also searching
for it.

Answer / suresh agravat

cold junction compensation means TC having 2 point one is hot junction an another is reference junction (not cold) once the hot point read the temperature mv dc will generate and it will travel from hot junction, reference junction then compensation cable cable to temperature transmitter. temperature transmitter having thermistor which read atmospheres temperature and it'll plus this temperature with main temperature

Answer / n.3vedi

CJC is that , we are making cold junction at 0 degree C by (any means) for measuring the perfect temp. of that hot body.

Answer / raja

CJC reason
01)0 degree compansation
02)third metal junction compansation.

Answer / nilesh karpe

CJC-IS the cold junction compantion.it is used in
thermocouple.two dissimiler metals joined together it forms
thermocouple.if we apply voltage tn one junction is hot &
another becomes cold Junction.
such Thermocouple generates MV output signal according
to metal characterstics.it gives 0 mv for 0 degree. to
measure actual temperature of the measuring point we should
remove the temp. of measurment envirnment for that the
compansation equals to surrounding temp. is provided and
used as 0mv.
This ref. 0V is generated by Three Methodes-A)Electronic's
0 V ref.,B)Ice bath Methoad,C)by using Peltier cooler .

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