| Complete digital
system, using micro processor and communication bus. Running at speed of 4
MHz or 1 million instructions a second. Ullage principle: Two
piezoelectric transducers in an arch facing each other, one sending
vibrations and one receiving at the other side. By the ultrasonic
velocity traveling through the oil, chemical and product phase at a
velocity, the receiver picks up and triggers a switch which sends a signal
to the micro processor.
Interface principle: by capacitive conductivity of water phase. Two
stainless steel electrodes set at an offset of the same point as the
ultrasonic with a tapered point to pierce the oil/water layer surface
tension. The water will conduct the electrical impulses to the other
electrode and triggers a switch, sending a signal to the micro processor.
Temperature measurement by Platinum Resistant Thermometer (PRT) of Class
B PT100 3-wire sensor. The PRT is embedded in one of the stainless steel
electrode. PRT gives a relatively linear output of resistance versus
temperature of about 0.3 Ohm per Degree Celsius.
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