detector

The IC is ideal for detecting the presence, absence or level of water or other conducting liquids. A detector determines the presence or absence of fluid by comparing the resistance of the fluid with the IC’s internal reference resistance. An AC signal is used to prevent plating of the probe. When the probe resistance increases [...]

A large area photodiode and current to frequency converter combined in a clear plastic 8-pin DIL package. The output is a pulse train whose frequency is directly proportional to the light intensity. The output is CMOS compatible (use a 3k3 pulldown resistor to drive LS TTL) and the frequency can be measured by pulse counting, [...]

A hole needs to be digged at the lowest place in the celler that have water incomming problems. The hole is about 0.5 x 0.5 x 0.5 meter, at the bottom a large water pump is mounted. Then the different water levels was measured, so we know how to make the sensors.
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