Hi All,
Please help out a complete beginner. I'm trying to build a very basic water level monitor but I think I'm trying to make it more complex than needs be.
To explain the "why": I'm a researcher at a University in Australia (Department of Biochemistry). Part of my job is to purify protein samples using a machine called an FPLC (basically a very expensive liquid pumping system). It draws liquid in from two sample bottles and pumps it through the system and various other components. Despite costing an insane amount of money (like all biomedical equipment) it does not have any way of monitoring when it has sucked up all the liquid in the sample bottle. This results in air being introduced into the system. This is not good. I'm pretty busy doing various other tasks around the lab and its very easy to lose focus and forget to continually monitor the water level.
So basically I'm trying to build a small widget which I place into the bottle that will sound an alarm when the liquid falls below a desired level so I can come running and replace the liquid or stop the pump.
My idea is based on a float type system: ie. a fixed rod with a small switch at the bottom which is inserted into a plastic test-tube and suspended in the water. While the water level is above the desired limit, the testube will float and press up against the switch at the bottom of the rod (or complete a circuit etc). When the water level falls, so will the test-tube, depressing the switch (or breaking the circuit). At this point I want an alarm to sound.
My thinking suggests that I need an inverter (NOT gate?) of some type so that while the switch is depressed, the alarm is silent but all the resources I've look at on the net seem to require a more-than-basic understanding of electronics.
So please help me out here (and contribute to biomedical research!). Any ideas which I might be able to implement would be great (the simpler the better). I'd also prefer to try and buy pre-made components rather than trying to put together complex circuits myself.
Thanks in advance for the help,
Mad__llama
Please help out a complete beginner. I'm trying to build a very basic water level monitor but I think I'm trying to make it more complex than needs be.
To explain the "why": I'm a researcher at a University in Australia (Department of Biochemistry). Part of my job is to purify protein samples using a machine called an FPLC (basically a very expensive liquid pumping system). It draws liquid in from two sample bottles and pumps it through the system and various other components. Despite costing an insane amount of money (like all biomedical equipment) it does not have any way of monitoring when it has sucked up all the liquid in the sample bottle. This results in air being introduced into the system. This is not good. I'm pretty busy doing various other tasks around the lab and its very easy to lose focus and forget to continually monitor the water level.
So basically I'm trying to build a small widget which I place into the bottle that will sound an alarm when the liquid falls below a desired level so I can come running and replace the liquid or stop the pump.
My idea is based on a float type system: ie. a fixed rod with a small switch at the bottom which is inserted into a plastic test-tube and suspended in the water. While the water level is above the desired limit, the testube will float and press up against the switch at the bottom of the rod (or complete a circuit etc). When the water level falls, so will the test-tube, depressing the switch (or breaking the circuit). At this point I want an alarm to sound.
My thinking suggests that I need an inverter (NOT gate?) of some type so that while the switch is depressed, the alarm is silent but all the resources I've look at on the net seem to require a more-than-basic understanding of electronics.
So please help me out here (and contribute to biomedical research!). Any ideas which I might be able to implement would be great (the simpler the better). I'd also prefer to try and buy pre-made components rather than trying to put together complex circuits myself.
Thanks in advance for the help,
Mad__llama