The usual solution is just a PCB with interleaving 'fingers', the water makes a conductive path across them - veroboard can be used as well, just link alternate tracks.
I had a look at the link about the PCB-based sensor posted during a previous discussion, it seems simple enough but I was wondering what kind of reliability issues would be associated with this due to water stagnation?
I had a look at the link about the PCB-based sensor posted during a previous discussion, it seems simple enough but I was wondering what kind of reliability issues would be associated with this due to water stagnation?
I had a look at the link about the PCB-based sensor posted during a previous discussion, it seems simple enough but I was wondering what kind of reliability issues would be associated with this due to water stagnation?
I think that if you tinned the PCB traces and tilted the board slightly so that the rain would drain off fairly rapidly, it would last for a long time. You might have to put some spikes on it to keep the birds off.
hi,
i am a new user to this .i am doing my engg. in india and i am in a situation to some project on electrical or electronics.if you have any ideas regarding these(headings,circuitsetc...,) please inform me as soon as possible
I've often wondered how the rain sensors on cars work. Some models can sense if it's raining, and adjust the repetativeness of the windscreen wipers to suit. Some better models go even further and seem to be able to tell when the windscreen will have sufficient rain on it to warrant a windscreen swipe! I am impressed by how quickly they respond to changes in the heavyness of the rainfall.
hi,
i am a new user to this .i am doing my engg. in india and i am in a situation to some project on electrical or electronics.if you have any ideas regarding these(headings,circuitsetc...,) please inform me as soon as possible
I would tilt it as mentioned to get the water to run off.
Use a MPU to measure the resistance. That way you could monitor the dry resistance as it changed (cruded up) over time. Use the same info to inform of the need to clean the sensor plate. Determine that a bird has gifted it etc.
Use a small fan or heat the plate to increase response time.
A modification to tilting bucket and reed switch --
Use a badminton raquet or similar lightweight frame with a cotton cloth stretched across --- works well in mist application in Leylandii propogation in greenhouses.
It probably won't stop corrosion completely but it might slow it down, at least by 50%.
With AC both tracks will corrode equally, unlike DC which will cause the anode only to corrode.
I don't know what frequency to use but higher is probab;y better and the capacitance doesn't matter providing its impedance is low compated to the water.