water leakage alarm consumption in stand by mode?
There is no "stand-by,zero". But, if I had designed such a thing, the 8-pin chip would be a µC which is running for about 100µs, checks the sensor during this time, and if no alarm had to be on, puts itself into deep sleep mode for about 10s.

It should be obvious you could only measure the deep-sleep current, which is likely to be less than 1µA, in that case.



EDIT: Schematic showing the currents and voltages due to a 99MΩ parasitic resistance against ambient.

This is to show how complicated it is to measure small currents.







simulate this circuit &ndash; Schematic created using CircuitLab

If you happen to know Ri and Rp exactly, you are okay. You can safely drop the additional 50mV (or whatever it is) and get the voltage drop over the resistor Rm and thus, the current into U1.

BUT, DO YOU?