Engine running detection

[shortbus=]

Automotive knock sensors are pure microphones. Discerning noise from knocking noise is done by the 'processing' circuitry in the ECU.

A Hall sensor is yes, another valid way.

While they are a basic 'microphone' they, at least the GM ones they made where I worked, were set to a certain frequency. Below that frequency they were dampened. Weren't supposed to give a signal until that vibration was met. Don't know how other companies do it.
https://www.azosensors.com/Article.aspx?ArticleID=50

 

[Externet]

Those could be tailored in piezoelectric thinness, reacting with more amplitude to the desired resonating knocking frequency and mostly unresponsive to other frequencies. Not the optimal type for the thread.

 

[Mosaic]

The OP needs to know if his animals are getting water. A running pump motor isn't really the solution.
This is quite reliable and can also tell the OP the flow rate.
**broken link removed**

 

[Sean the Nailer]

Considering the described application, and my experience on the ranch in northern B.C; I am thinking that you're looking for more of an indicator of water flow. To that, I would mechanically devise a simple "deer-scarer" of the typical Japanese bamboo sort. Though adapt it to simply be a flag that is held up constantly by the water flow, and it simply falls when the water stops.

Your prime mover is such a simple setup to begin with, that there is very little to work on. Unless you want to install power supply and circuitry for broadcast lighting, or even radio transmission, you're best off having a "visual indicator". Instead of a "water wheel" that would be constantly turning, think of a "water lever" that is held up by water hitting the lower/shorter end. When the water stops, the higher/longer end falls, due to gravity.

Now if you want that to hit a switch, which turns on a light, than is detected by a sensor, which processes a circuit, that sends a signal, that gets relayed through a transmitter, that gets bounced back by a satellite, that gets received by a dish, that gets uploaded to the intwebz, which then gets filtered by the NSA, before being wifi'd to your location, that is then sent to your BlueTooth, then by all means go for it.

 

[Tony Stewart]

HI Guys

I am looking for a way to monitor if a stationary engine (i.e Lister water pump) is running or not. These engines have no electrical except the coil to provide spark with an on/off button to interrupt the coil. I have a gsm commander that can measure voltage input or open/close state and send sms regarding the programming of said input.

I have thought about a magnet running on the fly wheel triggering a reed switch or infra red

Please assist with a circuit that will help me solve the problem

Thank you

The magneto is a variable reluctance device that generates the spark, which can create a large E-field that can be detected with an AM radio or audio amp and peak detector to sense engine running and pulse rate for RPM.

Also any electret mic and small amplifier can be rectified to create a logic level out.