big__col - I want to capture data from the engi...
I want to capture data from the engine gauges, RPM, engine oil pressure, gearbox oil pressure, engine temp, alternator. Will all of these, apart from RPM, be of Analogue type when connecting to my Halmets input? I'm thinking of installing the pair of Halmets behind the instrument panel where the gauges are installed to take a signal at the gauges directly. Any issues with this approach?
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pic of gauges...
I am working on the same conversion using HALMET. My understanding is pulse sensors are digital and voltage or ohms sensors are analog. For oil it could be either hall effect or variable resistance so each sensor needs to be determined if it’s digital or analog
Unknown User•9mo ago
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How does one determine if a gauge is analogue or digital?
Start with the engine manual. It should indicate the sensor output
Another option is to look up the gauge and pick up the signal after the gauge converts it to analog. Your gauges look very generic and there are lots of examples of how to do this on the internet
VDO is probably the most common analog gauge available so it should be well documented
When I get to reading RPMs in the next couple of weeks, I will share my code. It’s worth sharing these projects because of the available hardware that simplifies analog, digital, and 12v power to esp32 (HALMET)
Thanks @Tony so far I have bilge pumps monitored, and config is in place for 2 fuel and 3 water tanks...just need to connect them. 2 of the water tank sensors are not variable, instead they show when the tanks are at 1/4. 1/2 3/4 or full. I want to swap them out for 'proper' variable ones...
...and I'm always happy to share my config and code if it can be useful...
For the tank sensor, I used curve interpolation and an algorithm to calculate between two points. It’s not 100% accurate but works well enough. The problem is my tank is wedge shaped so need to know percent by volume instead of using a linear scale on the tank sender
I think to counter the issue it’s probably good to also add a counter for each gallon consumed so you can just get the ohms for every gallon and mark the ohms as percent
Yes, @Tony has been speaking words of wisdom. 😄
i have fuel flow/return meters in place, so this should be straight forward...
Unknown User•9mo ago
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Floscan
Anyone yet found a diesel fuel flow sensor that can work with small flows (~1 gallon/hour)? Seems like most only work with larger flow rates.
FCH-m-POM-HD -0,1 LPM 97478648: B.I.O-TECH Flowmeter
Low-flow Flowmeter from POM, for measuringWater, Diesel, Glycole and other non aggr. liquidsQ= 0,002 - 0,1 LPM, PNP, PLC compatible, 16 bar
Price was around 90 € excl. VAT and you need two to also measure the return flow. And if the return flow is substantial, you also need to measure the temperature difference and compensate thermal expansion. Many flow meters even include a thermometer but that one doesn't seem to.
That looks like it could work. Will take a closer look.