A
Hi,
as you mentioned the choice of sensor depends on many things such as corrosive, temp, ph, volatility. I'm working on a device that should work under drinking water so the water level sensing is important, but it needs only sensing the existence of water (not the depth). My major problem is corrosion because the device's body is a metal such as brass coated by chrome.
I tried some capacitive circuits, but they didn't work properly.
the problem is that the surface of device must be connected to 40Volt-DC (maximum voltage on the device circuit) and all capacitive circuits I've found work with an AC voltage on the probes, and I want to use the metal surface as one of the probes. I'd like to know that can I use the metal surface and another conductive probe as the capacitor surfaces and water as dielectric (while one of probes is connected to 40Vdc)? Or I should choose the second probe a conductor with a thin nonconductive material on it as dielectric (to avoid corrosion of the probe)? Do you offer any useful circuit?
thank you in advance.
as you mentioned the choice of sensor depends on many things such as corrosive, temp, ph, volatility. I'm working on a device that should work under drinking water so the water level sensing is important, but it needs only sensing the existence of water (not the depth). My major problem is corrosion because the device's body is a metal such as brass coated by chrome.
I tried some capacitive circuits, but they didn't work properly.
the problem is that the surface of device must be connected to 40Volt-DC (maximum voltage on the device circuit) and all capacitive circuits I've found work with an AC voltage on the probes, and I want to use the metal surface as one of the probes. I'd like to know that can I use the metal surface and another conductive probe as the capacitor surfaces and water as dielectric (while one of probes is connected to 40Vdc)? Or I should choose the second probe a conductor with a thin nonconductive material on it as dielectric (to avoid corrosion of the probe)? Do you offer any useful circuit?
thank you in advance.