At times, determining the fluid level can become very tiresome. When the stored containers are dark-colored, it gets more difficult. A special project fluid level detector has been developed to eradicate this issue. The circuit of fluid level detector comes with a limitation; it can be used to measure non-flammable fluids only. In this particular circuit, the fluid level detector is used in conjunction with a thermo-resistive probe to measure the levels of fluids under consideration.
A light is interfaced to one of the output terminals the chip offers. The glowing light indicates the low level state of the fluids. At this section, we can design the light to flash briefly or remain in ‘on’ state continuously. The circuit of fluid level detector comes with other benefits which include: transient protection, internal regulated supply, and short/open probe detection. In order to set reference values and supply a constant current for measuring, external passive components such as resistors, capacitors, and transistors are used, which are basic components in every electronic circuits. Here, a wire with high resistivity and temperature coefficient is used to develop probe. Nickel and cobalt alloy can be best solution available.
Basic key parameters of fluid level detector circuit are briefed below in points:
- Probe current reference voltage: – It is the voltage internally generated by the chip to regulate current to the probe. An external resistor is used to set the actual current value. Typical value is 2 V.
- Ramp thresholds: – These voltages are the threshold levels for the various tests and are in the tenths of volts range. They are measured by comparing the probe voltage (stored via an external capacitor) with internally generated voltages.
- Oscillator frequency: – The oscillator frequency is controlled by an external capacitor and this value is used to flash a warning indicator on and off. The approximated value is 2 Hz.
This chip/circuit can be used to measure levels of automotive oil, hydraulic fluid, and coolant. IT can also be employed in detecting Gas flow using the cooling of the probe by the flow of gas as an indicator.