Key research center of the refrigeration equipment, is on the quantity of heat, the heat of the service, the nature is cold, can get a cold, can have a good effect.
Thermocouple meter, it is a kind of measuring method of heat through heat conduction, although is not the main purpose, is one of the most convenient appliance.
under low vacuum, gas thermal conductivity is the key depends on the pressure, the higher the pressure, the molecular density is big, the thermal conductivity of the gas is better;
Conversely, when the pressure is less,
The higher the vacuum degree)
, the thermal conductivity of the gas.
Using the gas thermal conductivity and the relationship between the vacuum degree, made from various types of heat transfer vacuum gauge.
the commonly used thermocouple vacuum gauge measuring the voltage drop across R millivoltmeter G its features,
Thermocouple meter)
Each regulation of working current structure is simpler, generally between 100 ~ 120 ma.
Vacuum gauge tube heater and thermocouple in intersection T welding or connection.
Hot wire heating power from stable power supply, adjust its size by potentiometer W, should keep the hot wire heating when measuring current constant.
Known, heating current size.
When turn on the heater power, thermocouple at both ends of thermoelectric potential millivoltmeter G measurement is also available.
the thermocouple meter gauge tube manufacturing with differences, before using regulation, must first determine the size of the heating current, general regulation conducted in the factory before sealing.
Therefore, the regulation before didn't open, it's first working current is measured.
After working for a long time, due to reasons such as hot wire surface is defiled, make the regulation characteristics change, the heating current of the wire to determine again after cleaning.
the advantage of thermocouple gauge is measurable, steam and gas total pressure for indicator system of system pressure changes, the simple, easy to use, can also be measured over a long distance.
the downside is reading about gas species, thermal inertia, reading lags the change of the pressure, temperature changes affect measuring slightly.
refrigeration equipment, the application of thermocouple gauge at the same time, also in the innovative development of refrigeration equipment, in the near future, through the thermal conductivity of the energy conservation, to create refrigeration industry milestone, is still not clear!
