Chat freely about anything...
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By gggggggg
#65641 I have just purchased a electric fence energizer:
https://am.gallagher.com/au/products/el ... ins/G38111

It tells me it pulses 8000v about every second. I would like to
1) Monitor that, to ensure its happened at least once in the last few seconds (-i.e. is it still working).
2) Ensure the voltage has not dropped (did a animal touch it for a moment, or is there a weed on the fence)

How can I bring the 8000v down to a level that is small enough (even 1000-500v) that the ESP can process it and see differences at the same time?

I have no ideas at all. And Google and Arduino forums are giving me terms I do not understand. Given it will ideally be a ESP project, thought I would ask here.

thanks
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By rudy
#65648 The company I work for had been manufacturing electric fence energizers for 25+ years. I didn't have a lot of involvement with that portion of the business as there was no need to change any of the designs much. I did have to do some testing when there were questions.

There are problems when it comes to measuring the output. The most obvious one is the high voltage. The next problem is the waveform. The following is what I found on the web. At work I have better samples.

Image

Those are two traces for different energizers. One low power and one higher. The voltage is about the same. the difference is the pulse width. Those are waveforms from the fencer output not connected to a fence. The fence can have a significant impact on the waveform. The wire has capacitance to ground and that interacts with the fencer and you can get some interesting results.

I don't recommend using a voltage divider network. You would need to get special resistors that can handle the repeated hits of that high a voltage. I don't want to go into a lot of detail. The following is used for many testers. It is simple but does not lend itself to external monitoring.

Image


The fencer voltage indicator we had produced (we terminated the fencer line a few months ago) had a small transformer that safely converted the high voltage pulse to something more manageable for electronics to monitor. After some rectification and sampling we fed that into an ten segment LED bar-graph driver chip that was powered by a 9 volt battery. This was a handheld unit to be used along the fence line.

I have to go now, I will add more later.
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By gggggggg
#66060
rudy wrote:The fencer voltage indicator we had produced (we terminated the fencer line a few months ago) had a small transformer that safely converted the high voltage pulse to something more manageable for electronics to monitor. After some rectification and sampling we fed that into an ten segment LED bar-graph driver chip that was powered by a 9 volt battery. This was a handheld unit to be used along the fence line.

I have to go now, I will add more later.


Sorry for the delay, been away. This is very helpful. I presume this is similar to what you have described above:
http://www.ebay.com.au/itm/Gallagher-G5 ... SwXBFXPpoF

In theory I could crack it open and the LED inside would be 5v or similar, I could just connect my ESP to that. Though that would only tell me if its operating. Not if there are any issues cutting the voltage.

Alternatively this:
https://www.ebay.com.au/p/?iid=27224880 ... s&&&chn=ps
Might have a better way to get different status.

In theory, sound ok?
User avatar
By QuickFix
#66063 Just trying to think along, so don't shoot me as I don't have any experience with voltages over 380V. ;)

Since it's a pulsating signal, couldn't you use a simple coil with a zener (for limiting/protection) in parallel?
That way you don't have to mess directly with the hi-pot of the energizer.