Hi if you remember this electric fence controller I found in the dumpster and if you don't, well I'll link it in down below at the end. if you haven't seen the video, it was quite popular, unfortunately it was broken, but it was like quite an interesting tear down of this thing. Quite an old unit was designed and manufactured by Pact and Technologies here in Australia who's one of the world leading designers and manufacturers of electric fence controllers and as it turns out, I was able to get in contact with the founder and CEO and chief designer of our Pact in Technologies Paul Thompson and we actually did an Amp Hour episode talking about the history of this unit, how we designed an electric fence controller design, in general, all sorts of things about lightning protection and tons of interesting technical discussion and highly recommend you check it out. it's linked in down below over at the Amp Hour comm you can get on your iTunes Eze and you I Heart Radio is your favorite podcasting, apps and all that sort of stuff, but he was actually rather embarrassed by this design.

He didn't think I was very early design, didn't think it was very good so he said hey, let me send you in one of our new Bobby Dazzler and here it is. Look at this: this is the JV Am B8 and Jva is there like you know, house brand but it's actually packed in technologies in Queensland Who actually designed here in Australia who design and manufacture these locally and once again it's like it's got Wi-Fi and everything else and in the podcast out Paul talks about what how farmers they want to you know, wake up in the morning and use Wi-Fi and an app on their phone just to check that their electric fence is still working and stuff like that anyway. Paul Thought this would make a more interesting teardown and I'm sure it would. So you know what we say, you're on the evey book.

don't turn it on, take it apart. Still got these giant thumb terminals. look at this. Yes has a big hole in there for the wire to go through our fantastic so you know it's not that these are high current at all.

Um, in fact they're quite low card they're designed it not to kill you. but yeah, you don't want to be touching this because it's not gonna be pretty anyway. I Love the enclosure, it's all like weatherproof and everything else. Absolutely fantastic.

Here we go. This is an Eight Julie Sixty-six raided 12 to 24 volts DC in and you know it's only ten watts so there's not a huge amount of like actual power behind it, but eight joules you know that'll wake you up made in Australia No workers and as I mentioned in the previous video pack, Ton actually do really amazing repair guides for these things. and Paul talks about that in the podcast episode about why they do that and they have an eBay store that sells spare parts for this thing like output transformers because they're a custom job II and really interested in discussions on their about our transformer design in a Greybeard transformer design and stuff like that. sell transformers and output caps and and other around spare parts for their products so that people can fix these themselves.

Here we go: I have not powered this thing up since I got it so it's gonna be discharged I Love that OH bah-bah capacitors they're floating Oh little rubber baby buggy bumpers. Oh love it. Anyway, look at the bigger custom output transformer here and a very similar design and construction really to the previous unit. We've got the output Raisa board here with the output capacitors and also limiting resistors as well.

We've got our huge more protection down here all in series. Absolutely fantastic. We went over the all this sort of stuff in the previous one so it's going to be very similar now. Paul Talks about this in the podcast as well and it's are fascinating.

This is of course an optocoupler do-it-yourself optocoupler the previous design as you saw in the last teardown and actually the old one had just some heat shrink tubing going across. but now they've got this custom like injection molded plastic thing. but it's basically it's just a it's an infrared LED over here and just a photo trenny over here. and that's the only way that they can get that decent vote.

high voltage isolation. and of course they get it. Measures the voltage back across this as well. It's not just like that it's on or off.

They can actually measure and monitor the output voltage as well. But yeah, that's nice. And I Love it How they give you the error codes here soon? that's some LEDs Is it? Unless they have a seven segment display somewhere, this is one of the runts of the litter here. The eight jewel looks like it goes up to 20 jewel.

yes A. In the podcast, he talks about all the various US standards and things like that that these things have to meet in order to essentially not kill people are for starters Anyway, isn't that a big nice output joke? Wow Love that that actually it looks like it's an ear cord. Joby I Don't see any ferrite in that and there. Our monster output transistors down in there.

She'll be able to get a part number on that and let's just focus in on that. There you go, there's a part number for those playing along at home. Now this thing is a two-stage booster. So here's the first transformer that actually boosts up to like the six seven hundred volts at something like that that charges up our main caps here.

and then of course the big output transistors here. They just dump that into the in a very controlled way by the way. and Paul talks about that in the Podcast about the pole shape and things like that. Maybe we'll be able to measure that here.

Perhaps when we power this thing up, Say that they just dumped the energy from the capacitors into the transfer through the transformer and into the electric fence. On the output and the pulse shape is are very critical for this thing and they go through pretty much a like 100 percent charge discharge cycle. Like each second for these caps, the output ranges goes bang bang bang. So these main storage caps are quite different to the ones that we saw in the previous one.

They're not made strong your anymore or by please' unfortunately. But anyway, these are our potted ones with that leads coming out. As I said, they do sell replacement ones and they decide to put these on stand offs on the board like that presumably like to free up space. Probably make them easier to out replace as well because as I said, but they sell spare ones of these on eBay if the Apple Capps eventually fail.

you know in five or ten years or whatever because they these getting a hard life, they really do when they're just dumping everything once per second, charging, discharge it once per second for like you know, 24/7 for like a decade. Yeah, eventually we're out so you can simply replace those and get them by them as a whole assembly and go plug them in. Very nice and all the Pic processor fanboys go wild. And also in the podcast you Gotta listen to it's fantastic.

Paul talks about love There something fell down. Anyway, let's continue. He talks about why they actually use specifically use a microchip part and it's a very interesting story. Actually, there's the Wi-Fi module for those into that sort of thing.

It is Jva branded so they do actually I get that specifically custom-made for them. it's the Wii and nope, nothing really doing on the underside that makes sense of course. And there's no need for our cutouts and things like that because you have adequate, more than adequate creepies distance across the PCB. It's just yeah, it's a massive and one technique you've seen me use many times is LEDs actually reverse mount LEDs on the top of the board.

so there. But then when the cord bottom emitters and you just put a like a hole or a slot cutout in this case in the bottom of the PCB and then that just shines through the front here. looks like they didn't even bother with light pipes, don't even need them, it's just all custom molded into the plastic case so that's really nice. Bottom emitter is really handy because you can play some with standard SMD components and just goes out the other side of the board.

You have to dig around with light pipes. great. Now, although we don't have the schematic Paul's very kindly provided. like an overview block diagram of how this thing works and it's a pretty simplistic.

The main charge capacitors are here that store all the jewels. In this case, we've got our 230 micro farad at nine hundred volt caps here and I just realized that another reason that you'd have them sticking out like this is so that you can put larger caps in there for the bigger jewel models presumably. So maybe the you know one size fits all transformer and then depends on the model you got. You choose different caps and then just tweak the firmware or whatever.

So yet that wouldn't surprise me. anyway. now we've actually got to pick process. what is the main pic here and another one is a Watchdog peak and that could be a little tiny one over there or something.

perhaps haven't looked at the the like Exact part that little tiny a pic. you don't need much and that does that. Watchdog at Control for Safety and Poor talks about that in the podcast of course. So we've got 12 to 24 volts DC in and as I said, we've got the first stage step-up transformer here.

that's just a MOSFET doesn't need to be hugely grunting, not like the output Scr's over here and then output diode and then some feedback out resistors here to allow them to monitor the charge voltage on the capacitor bank as itself. And of course, this has to be grunty enough to charge fully charge. These things to get all your eight jewels into there within the second or whatever the cycle period is. And then we've got a output choke here, and that's almost certainly that air cord job' there.

And then you've just got a Scr driver and a one or more SC as in here, which then just dump all the energy through the primary side of your output transformer here and then that's just tapped off at a higher voltage. and the SCRs They're going to be down in there as per the previous design. so the layouts are very similar. And then, of course, we've got a full voltage of feedback here.

As I said, and basically, it works in the linear version of the letter. Even if it didn't, you could actually compensate for that in software. and you can basically read back the output voltage with your own custom high voltage opto isolator. Beautiful thing of beauty: Joy Forever.

So although the basic concept is fairly simple, if you listen to Paul talk about how they developed are these things over the years, there's a lot of art and science which goes into these. The pole shape, the transformer design, output protection, and input protection of the charge/discharge cycles of the capstone. All sorts of stuff and lots of intelligence in the firmware to handle all that sort of stuff. The really not a fan of these connectors I Don't know what the deal is, they're industry standard theme, huh? All right, so let's pal this bad boy up, shall we? I've got my 1k like 100 watt Ry around resistor here and it's got some open coil windings on there, so maybe I don't know.

You could do the maths in your head right now to see if that could potentially arc over each one of those. That might be kind of cool if it could. 24 30 24 Kilovolts that doesn't makes it right now. that's probably firmware version I'd say something like that one Pkware whatever that means one we're ready to go.

Let's pair on. and there you go. It's ticking over. Energizer: Okay, LED 7.9 kilovolts, 12 joules there.

so it like sticking over that once per second. Unfortunately, we're going to no Sparky's on the resistor, but well anyway, it is dumping that into that 1k load. 12 joules each and every time. The kilovolt reading on here that's actually measured directly from the output terminals via the opto coupler and the 12 joules is actually the measured energy on the capacitors themselves.

So this was supposed to be rated 8 wasn't it? We've got 12 Bonus. All right, let's see if we can get some sparkies happening in here. Give it a bowl. Not exactly the best point source there, but good enough restore and we're ready to dump.

Whoa. nice look at that. Ah, terrific. need to shoot this in with my high-speed camera.

Wow Oh wow, Well you. It's just like a bright flash and the energy is gone. It's actually safe. It actually discharges straight away as soon as you turn it off.

No workers? Yes! I have actually measured it. Okay, let's try and nab some high speed. I've got my Chronos 1.4 at serial number seven. It's one of the original Kickstarter units.

Absolutely fantastic high speed camera. They're up to version two now. But anyway, I've got that set to 1280 by 720 at 1500 frames per second. We'll give this a bill.

Okay, more light required I think and higher framerate because I just previewed that video and I only got like a couple of frames out of that that were usable to go for 640 by 240 at 8800 frames per second. Alright, this is just over eighty eight hundred frames per second and watch it bang in one frame. There, you saw it arc over and not partially just one single frame off. Then on and it forms that plasma arc which sustains it for a bit until the cycle goes back and itself extinguishes.

Cool, huh? So can you or me to go to 6,000 volts? My baby can look at this? The Triplets: 6:30 N/a 6,000 volts DC and AC mode. So I'm just gonna switch it on Wah wah wah wah. We're not gonna see it diddly squat because the policy is too quick. That needle ain't even budgin.

Alright, let's blow the snot out of this $2 cheapy that we got in the mail bag, put it to a thousand volt range and well, let's pair it up. Of course, Eight Joules is not exactly like though. I think we have 300 with our Doug Ford's one where we blew it up. But anyway, there we go.

Boom. You can hear it arcing inside. it's just continually arcing bang bang can't smell it I can see I can see I can inside or we get now red status there - and there it is. It looks like it's all the actions happened up in the chip.

I'll look at the blob I think we have a chunk of the blob taken out and a big Ernie Bernie Mike right there I can smell that magic smoke. Okay, I'm gonna try that again. Up close here we go. Boom Magic smoke escaping each time there we go.

Fantastic. Try that one more time. Whispers smoke going up. Fantastic.

And on the bottom side here there's a small little Ernie Bernie mark just between a couple of contacts on the rain switch and that's one of the common our failure points All right. I'm gonna sacrifice a famously rugged meter here. The BM 2, 3, 5 fingers crossed I do have it on the full output here. by the way, we can take a half output but I'm gone for broke is I I Have no idea of like the pole shape of this compared to the IEC standard.

Naw that am I doing alright? Here we go. Nope. It's 6.9 kilovolts and it's not overloading. There's no over.

There's no red status there. It is surviving that. Just hunky-dory That's what you get when you get input protection. That's the most kicking in.

Nice. Sure enough. I Just checked it on DC volts and it's bang on so it survives. No worries whatsoever.

Alright, let's try a 121. GW This is a lower rated meter cat rated meter than the BM at 2 3 5. So let's see what happens. Ping Ping Ping ping.

There's no red status thing and I checked and that survived just fine as well. Measuring bang on. So yeah, I don't know. Let's see if we can actually measure a pole shape.

Alright, so we've got our 1 Cayne resistor in series with a 50 Ohm here. I've got my Eevblog high voltage probe here and we'll just single-shot we got one. There's this initial spike up there like that, which goes to let's call that full-scale just back down and then BAM goes up again and then discharges pretty linearly. like that.

There's a little bit of undershoot of course, and that's it. So Ed. then that pattern repeats every second. So yeah, is that a typical pole shape for a electric fence controller after a sport and a 50 microseconds per division? We're talking less than 200 microsecond pulse here, so it's not much.

and if we choose the other middle terminal there, that should be half voltage single-shot and yep, there you go half I It's just half amplitude basically, but it's a little bit a little bit more wobbly there is that you to the output network. so there you go I Hope you found that as interesting as I did. Thank you very much Paul From Pact and Technology /jv A who's the designer of this thing and manufactured in Australia you bloody Ripper And absolutely fascinating these electric fence controllers and the technology that goes into them. As I said, listen to the podcast, it's absolutely fantastic with Paul so that's LinkedIn And down below definitely can't link it at the end because can't leaking audio podcasts because Youtube doesn't do that sort of thing really.

So anyway, if you enjoyed it, please give it a big thumbs up. And as always discussed down below and yep, I'm gonna plug it every video my library channel 13 now a thousand subscribers. Check it out. Catch you next time.