Henry - I'm quite please that I've managed to g...
I'm quite please that I've managed to get my engine RPM onto the N2K / SignalK with a cheap Aliexpress converter.
I'm new to Node-Red so still learning, I managed to make an average function to smooth it out a bit (RPM was jumping around a bit).
But next challenge is getting it to read zero.
When the engine is off the unit turns off stops sending a signal.
I'm thinking I could implemenet a Node-Red function that injects a zero and then an IF function to choose the larger of the two.
(the functions aren't quite right as I'm practising at home so online node-red doesn't have all of the signalk plugins).
But any comments / thoughts / code corrections welcome.
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10 Replies
If there is no data then that isn’t really zero. Something like null or displaying —
https://cookbook.nodered.org/basic/trigger-timeout
And like @Tony said send null
Cheers, managed to get trigger and timeout working well. I just went for zero for ease, means dial shows zero which (when the engine is off) is correct
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@Henry May I ask what sensor hardware you used to accomplish this?
A cx5003 from eBay engine nmea 2000 converter. Hardware wise very easy to install.
Wow, that is an inexpensive device!
What I’m particularly interested in is how the rpm is measured. Is it connected to the existing analogue rpm gauge?
We've just installed a new balmar alternator and regulator. That has a tacho output which is a pulse. But would also work off a normal alternator, just takes the tacho pulse and you set the dip switch to set the frequency.
The tach output on the Balmar regulator doesn’t work for me once the battery is charged.
Have read that is a common problem. We don't motor that often and have a 540ah lithium battery so will take a while for engines to get to float.
Worse case for another tacho to the flywheel.
Yes that is my plan. Dedicated tacho always working