The cloud water content meter (LWC/TWC probe) designed for in situ continuous measurement of both total (liquid plus ice) water content, or TWC, and separately liquid water content, or LWC in clouds and fogs.
The general principle of cloud water content measurement with the instrument based on the principle of maintaining a constant temperature of the sensor. The device consists of two electronic units, cables and the combined sensor mounted on a rack in front of the fuselage. The sensor unit has two collector evaporator — a streamlined cylindrical shape, which responds only to the liquid phase and the other recessed shapes, such as inertial traps, which responds to the total (liquid + crystals) water content.
The device is known in the world under the name of the Nevzorov LWC / TWC probe, as the best instrument of appointment. Nevzorov LWC / TWC probe is widely used for measuring the total liquid-water content of clouds, and both Russian and foreign researchers in Canada, the United States, Britain and Germany.
The devise is designed for installation and operation of civil aircraft having an air speed of 70 to 200 m/s and equipped for flying weather laboratory and / or have a means of recording the output signal. The temperature range studied clouds is between +30°C and -60°C.
BASIC PERFORMANCE DATA:

• The limits of measurement of water content in clouds at aircraft airspeed of 100 ± 20 m/s and the characteristics of sensors listed belong:
lower limit, g/m3, not more than 0.003
upper limit, g/m3, at least 3
• Standardized performance of sensor probe:
The sample area, cm2:
total water content probe 0,5 ± 0,1
probe liquid-water content 0,3 ± 0,05
The outer diameter of the collector-evaporator (mm), not more than
total water content sensor – 8,2
liquid-water content sensor – 2
Resistance between the sensing elements at a temperature of 90°C – 1,5-4 ohm
Sensor bridge ratio 1,00 3,99
• Limits the output voltage, V, 0 — 10
• Output resistance, ohm, not more than 1,0
• The time constant of the circuit output voltage, from 0,01
• The maximum setting temperature of the installation sensors, 100°C
• Power supply, V, +27 ± 10%
• Current consumption from the power supply, A, no more than 12
• Dimensions of each electronic unit, mm – 330*60*380
• Total weight – 1,1 kg