Connecting hall effect sensor

I have a emonTH that I want to connect to a gas meter (my own) that is in series with our actual gas meter. I have the reed switch module for this meter (Sensus Cubix U6) but am getting an inaccuracy of 3% a day in readings due to I believe is bounce related.

I am looking at swapping from reed switch to hall effect.

Wanted one that was low power, 3.3v and would be happy with the existing pull up resister.

I’m open to ideas.



Have you tried adjusting the ‘debounce time’ - PULSE_MAX_DURATION in the emonTH? That is essentially the time (in ms) for which subsequent pulses are ignored after the first edge is seen. It needs to be long enough to cover all the contact bounces, but short enough not to miss the next real pulse. I was a bit surprised to see it’s set to 50 (ms), as I thought the same in the emonTx is normally 100 or 110 ms.

The data sheet for your Hall effect sensor does say “low sensitivity” - I’m not well-versed in magnetic units, so I’ve no idea what to expect nor how close you can get that to the magnet. It’s something to check if possible.

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Many thanks for your reply @Robert.Wall

I’d looked and googled for debounce and read up on how the v2 incorporated debounce but I think I’d missed the actual register to change - I’ve now found it in the source.

I’m now reading up about compiling up my own version thankfully I’d bought the USB interface, just wasn’t expecting to need it quite so soon :grinning:

It’s a good point about the sensitivity of the hall effect sensors, With the price of them, I’ve bought three ranges of sensitivity anyhow to try each type and see how successful they are.

All the best