I am looking for a hardware answer to the following problem. Hopefully something USB.............I need to:
(1) control a solenoid value which is 12VDC with 0.50 Amps
(2) monitor flow after the solenoid has opened with a Vision 2000 Flowmeter
Power supply 5 - 24 VDC
Power consumption Approx. 8mA
Output signal Frequency open collector (NPN sinking)
Output current Max. 20mA
Apparently it pulses at 2200/liter that flows through it. There is no way that a liter would make it through in one second. I would place it more like minimum 6 seconds for a liter.
I have been playing with the idea of using Data acquisition, data logger boards, etc. but they have too many features and are way too costly $200-500. I want a solution under $100, preferably like $20.