Razlika med termoelementom in toplotnim uporom ter metodo izbire uporabe

Temperaturni merilni instrumenti se pogosto uporabljajo pri vsakodnevnem delu . toplotni upori in termoelementi so temperaturni merilni instrumenti ., ali naj se za isto lokacijo merjenja temperature izberejo termični upori ali termoelementi?

Struktura termoelementov

There are three shapes of thermocouple front joints. According to the type, wire diameter and application temperature of the thermocouple, gas welding, butt welding, resistance welding, arc welding and silver welding can be used for welding. In industrial applications, in order to facilitate installation and extend the service life of thermocouples, the method of adding sleeves is usually posvojen

Rokavi so na splošno razdeljeni na zaščitno cev in oklepni tip .

Termoelementi z zaščitnimi cevmi se uporabljajo za vstavljanje jedrne žice in izolacijske cevi termoelementa v zaščitno cev . Zaščitna cev lahko vzdržuje mehansko trdnost termoelementa, hkrati pa prepreči jedro žice pred oksidacijo in korozijo .

Oklepni termoelementi

The measurement principle of armored thermocouples is the same as that of thermocouples with protective tubes. It replaces the insulating tube (ceramic) with a slender metal tube (called a sleeve) and uses magnesium oxide (MgO) powder as the insulating material. Because of its thin outer diameter, it is easy to bend and is more suitable for measuring the temperature of the back of an object and narrow gaps. In addition, compared with thermocouples with protective tubes, its response speed is more flexible. The outer diameter range of armored thermocouples is very wide, and it can be stretched into various sizes from 8.0 mm ф to 0.5 mm ° . Tanjša jedrna žica je raztegnjena, spodnja zgornja meja skupne temperature. Na primer, zgornja meja skupne temperature termoelementa tipa K z zunanjim premerom 0,5 mm l je 600 stopinj in 1050 stopinj, kadar je zunanji premer 8,0 mm l 8,0 mm l.

Struktura toplotnega upora

Obstajajo tri vrste komponentnih oblik toplotnih uporov, trenutno pa je tip keramičnega paketa glavna . tip keramičnega paketa se uporablja za toplotne upori z zaščitnimi cevmi in oklepnimi termalnimi upori . Premer gole žice s keramično in stekleno žico se približno desetine mikrone in o približno desetini mikronov in se mikrone mikrone, približno desetina mikrofrenic, ki se mikrone mikrone, in se mikrona mikrona in mikroba 0 . 05 mm.

Razlikovanje

Although they are all contact thermometers, they have different temperature measurement ranges. Thermocouples are used in high temperature environments because the output thermoelectric potential in the medium and low temperature areas is very small (it can be checked by looking up the table). When the potential is small, the requirements for the counter-interference measures and the secondary table are very high, otherwise the measurement will be inaccurate. Moreover, in the low temperature area, the relative error caused by the change of the cold end temperature and the ambient temperature is very prominent and difficult to be fully compensated. At this time, at medium and low temperatures, the temperature measurement range of the thermal resistor is generally 200~500, or even lower.