OK, if that is accurate then the sensor output is 112.5hz. Why don't you just measure the frequency from the sensor at 1500rpm?but my guess is around
15 liters/minute at 1500 rpm.
SG
OK, if that is accurate then the sensor output is 112.5hz. Why don't you just measure the frequency from the sensor at 1500rpm?but my guess is around
15 liters/minute at 1500 rpm.
Sure why not. Change C to .1uf for relay closure below 50Hz.But I could built the circuit with the LM2907 ic and change values at a later date to suit.??
Change R to 56K.... leave C at .1ufHence the relay must become energized at a minimum of 12 l/min.
The output will drive 50mA, so that’s most 12V relays and quite a lot of buzzers,. As you need the output energised when the speed is lower than the threshold, use the n/c contacts on the relay, saving a resistor and a transistor; but you do need the 16-pin version, with pin 11 biassed to half supply.using the LM2907 speed switch. From the data sheet:
10.2.2 Other Application Circuits This section shows application circuit examples using the LM2907-N and LM2917-N devices. Customers must fully validate and test these circuits before implementing a design based on these examples.
View attachment 216262
I disagree with the above. Never been a fan of having a relay normally energized and don't see the need for the 16 pin version.use the n/c contacts on the relay, saving a resistor and a transistor; but you do need the 16-pin version, with pin 11 biassed to half supply.
For the 8-pin device, the non-inverting input to the comparator is connected to pin 1, and the inverting input is connected to ground.I disagree with the above. Never been a fan of having a relay normally energized and don't see the need for the 16 pin version.
SG
Are you in the USA?I can get the 8-dip type easy,
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