Effective false lighting filtering

lightning

#8

I already spend many hours on reading all kind of useful stuff from this community. Very informative indeed.

False lighting is one of the issues that people haven trouble with. Because of the false lighting alarms, people are even disabling it, which kind of defeats the purpose of having a sensor. Other people try to rotate it, or move it around in order to minimize the false alarms. But I figured that the sensor is very sensitive and for some situations it is very hard or impossible to find a spot without false lightning detections.

My suggestion to only raise an alarm and suppress or withhold the first lightning from the data unless there is a second detection within the next 10 or 15 minutes, seems simple and effective enough and wouldn’t effect any real thunderstorm alarms. (except that the alarm might come a bit later for storms with very infrequent lightnings)


#9

I think its discussed or implemented here Lightning Alerts logic


#10

That discussion is about the logic that is currently implemented to prevent people from getting too many alarms when a real storm is present. The suggestion mentioned above is to prevent alarms when no storm is present.


#11

So you know WeatherFlow is actively working on the firmware to correct false alerts.


#12

It’s actually more sophisticated than firmware tuning. Our applied machine learning / continuous learning systems can inspect data and should (eventually) be able to disqualify and/or correct a range of suspect data. This is a double edge sword as instantaneous lightning alerts are really cool…but to apply a layer of data inspection to filter data takes time, thus delaying “instantaneous” alerts. Hummmm.


#13

indeed, real time alerts are super cool, but for people that are unable to find a spot or orientation that suppresses the false alerts this feature might be really appreciated. Note it only delays the first alert and only by as much as the time between the first and the second strike. If the second strike isn’t detected, the first alert will not be shown at all (suppressing the false detection), if the second strike does arrive you can still report the first strike, but indeed a bit delayed.


#14

Sounds like a good conditional filter to build with IFTTT.


#15

perhaps, but given the number of people with false detections, it is worth considering to be part of the supplied app.


#16

It’s a small number and initially on setup. Once the Air is properly positioned false readings drop to zero.

I have not had a false reading all this year.


#17

Think I wrote this numerous times here and on other fora. If you have a little am radio (old school type) tune it to some free frequency and listen to ploks (strokes or distant disturbance)

And now walk around your house and appliances and enjoy all the noise (little transfo, telly, induction plate, computer, printer, your screen … … ) you will be amazed by all the things that produce what you call false positives.

Now that you know this, go back to where you air is and do the same around it (all direction and don’t forget up and down) and try to find the sweat spot where there is least ‘noise’ …

And don’t think you’ll find it within minutes … you’ll be busy for several weeks because what seems ok at a moment can be a complete mess 10 minutes later when a neighbour starts his plasma tv … a small shop uses some machine that sparks … don’t even hope for a sweat spot when you have a welder nearby …

You can filter all you want but that will never work in the end. Blitzortung members know all to well, after trying all kinda tricks, you finally end by reducing noise candidates to a minimum in your house (change transfo, light bulbs (especially those economic ones, most leds are ok btw …) and then you go walk around the house and try to negotiate with neighbours if nearby … and finally you start again to find the sweat spot …

Blitzortung devices can detect 5000 km and more in some cases … so imagine how to filter which such sensitive devices ??? And the little device in your air is pretty sensitive to …


#18

Don’t know about sensitivity of WF gear. Still waiting for mine but I run the Blitzortung Blue receiver in Galway.
They are very sensitive to stuff like electric fences, switch gear and arcs. Even a cigarette lighter with a piezo sparker held close to the antenna will cause a false.
A lot depends on antenna positioning. A lot of noise can be subdued by rotating the antennae or moving it. It can also be shielded.


#19

I know. But i don’t think it comes from my house. It happens when I’m not even at home. The only thing that turns on during that time, is the fridge. Now surely that will induce a small emp, but the air is outside and at least 10 meter away from the fridge. If it were the fridge, it most likely would generate more false detections. But even one or two false detections each day makes it almost useless.

Delaying only the very first alarm doesn’t do a lot of harm I would say. A storm with only one strike might be interesting, but is not worth giving a warning for anyway.


#20

Funny story - I have had a few false lightning reports this weekend. Turns out that one of the fittings on the air compressor in my garage had a tiny leak, causing the compressor motor to cycle on/off about once per day and generate the spark that was picked up by the Air on the outside garage wall…


#21

New AIR feature: air compressor leak detection! :wink:


#22

Why think small? Roscosmos certainly can use a leak detector for their Soyuz spacecraft, especially one that also triggers when detecting the arcs from the motor of an errant electric drill at the factory… :thinking:


#23

What kind of heating system is used in your place ?
As well, oil blowers have known emp issues and start statistically those days. :wink:


#24

central heating. it has a pump that for its own reasons starts up for a few minutes at 6 in the evening. It’s about 25m away from the unit and doesn’t correlate with the false readings. Even if it did, what can I do, the pump does his thing as it is designed to do that.
I have no idea what an oil blower is.


#25

He probably means that the oil burner has a piezo igniter that would false the lightening detector. It causes a spark between the electrode and the fuel jet that ignites the fuel spray.


#26

Some (maybe most) oil furnace burners have a high voltage transformer that causes an arc between a pair of electrodes during the ignition phase. Usually they also have a CdS photocell and a timer circuit that shuts off the arc when it sees that the oil spray has ignited or after a period of time with no fire. Ignition or not, you have a small spark-gap transmitter running whenever the furnace starts. So this certainly has the potential to cause false lightning detections.


#27

Thanks dan for your supplements.
Sometimes it’s hard to hit the bull’s eye in translation :wink:
So I was able to learn :slight_smile:

In addition, as I know, gas heating systems have a similar mechanism.