Hi, it's tar down time. We're going to take a look at this a Ac11 socket tester. Now we've seen AEG before and they rebadge a bunch of um, other companies uh products. so I haven't looked of who originally manufactures this, but it's a main socker tester.

It's got an Aussie plug none of that Yankee or European uh rubbish and it's one of these whizbang fancy ones. and it's also got non- cont voltage tester as well. So let's power this thing on and Tada and you'll notice it has this actually shows up better on camera than it does in real life. In real life, this is really faded and washed out orange.

It reminds me of the like really crappy gas plasma displays in like the late 80s early 90s. I Think uh, Tashiba used to make them on the Tashiba laptops, but uh, it just it looks very sickly and washed out. anyway. Um, main soccer testers are very interesting.

This is a fancy panty one and here is your more traditional, very simple one: I've had this for at least 30 years so I'm actually going to tear this one apart. Yeah, they've got three indicators here. You don't need any power like you do with this one. This one's battery powered here.

Fancy pancy. I Wouldn't rely on a battery powered socket tester anyway. the whole idea of these things is that they're designed to test the wiring of your Main's wiring and tell you if it's correct to tell you if you've swapped active and neutral active, an earth, or something like that, or you're missing an earth or uh, something like that, So yeah, these soccer testers very handy. Um, to have one, you should should have one.

and I built one of these when I was a kid. So inside one of these is very simple. They're just basically a diode in series with an LED here and a series uh, dropper resistor. in this case I Think this one might be a neon bulb instead of an LED But um, yeah, the new ones are lead.

Yeah, it's just got one between there, one between there and one between there and a triangle shape like that and that gives you all these different things. So if your red and green lights come on, then it's okay. and if just the green light comes on, it's no neutral. Um, is unsafe so you've got a broken neutral and if the green and orange come on um, active and Earth have been re reversed unsafe obviously.

Um, and if just the Orang is on active on Earth and Earth not connected unsafe. And then if orange and red are on active on Earth short or polarity reversed unsafe. and if Red's just on on its own, then you've got just a missing Earth connection on there. And these are really simple things.

So anyway, um, I'll just crack this open quickly. Tongue at the right angle. There you go. That was a bit easier than I thought.

So let's have a squee. And yep, I was right there you go. This is a neon bulb version like that. So this one, um, it just has dropper resistors and neon bulb and that's it.

Yeah, so this one is really crude. but yeah, your more modern ones, more modern crude ones will have a lead and diode in series and this one is Kamagata. Yeah, um, that was probably just pulling that out and it's just broken off there. but there's nothing in them really.

So we'll tear down this fancy pancy one. see what makes a tick? Obviously, it's going to have a micro in there. It's going to have a non- contct voltage tester circuit just like you've got like in your regular um, voltage to protection uh, sticks or something like that. So this will be really, uh, fancy.

So if we have a look at a more modern passive one like this uh, fluke St 240 plus leave it in the comments If you want me to get this and uh, do a tear down, it's basically the same thing. It's got three indicators there. It's got an Rcd uh test button which uh, this one does as well. Uh, which just puts a suitable resistor on uh between active and Earth which then will trip your 30 milliamp Earth leakage circuit breaker or residual Uh current device.

As Rcd says, and once again, if you've got the two leads on, then it's correct. If you've got the Earth fault, only one will be on neutral fault, the other Leb will be on if they're all off, your lives are broken or you've switched the PowerPoint off or your circuit breakers tripped or uh, something like that and the other two which includes a red lead instead of a green one I Guess live neutral reversed or Live Earth reversed. Now what you won't notice is that uh, this these simple uh testers like this, they can't test a uh neutral Earth swap because most modern main systems use the Men system or multiple Earth neutral system which means that the neutral is bonded to the Uh Earth usually back at your fuse box in your house or something like that. Not sure how it works in a building like this I haven't actually checked my power board? Does it go all the way back down to the substation in the basement of the building? Or or not I'm not actually sure.

leave it in the comments down below if you're an industrial electrician. Anyway, these simple devices which include these ones, they cannot uh, detect an earth neutral swap unfortunately. so that's one of the downsides. and there's tons of these available.

Here's another Stanley uh, brand one and it works in exactly the same way as that fluke one. but this one actually tells you this unit will not deter detect Earth neutral reverse? There it is there. so trap for young players. Anyway, let's go back to this Aing Ac11.

It's got two AAA batteries in it which Powers it here as you can see so let's power that up again and you can see all the indicators and they've got another filter on that LCD to give you green like that. Um so green is brighter than the orange here. but this one here actually tells you the Main's voltage I.E line and neutral here. it also tells you the neutral Earth voltage.

So not only that neutral and Earth is connected but how well is it connected? I.E What's the resistance of your neutral? uh Earth and it gives you the voltage here. So let's you actually plug this in and try it out. A sorry I Forgot to plug this old one in but trust me it just lights up red and uh green. So here we go let's plug it in and and it is correct.

So it took a few seconds there so obviously it's m the micros are doing doing the detection and stuff like that and um 245 volts here in the lab that is normal and uh oh there you go. 7 to one volt neutral Earth but as I said, that'll depend on your how your system wi up. I'm in a big commercial building here so if it's bonded right back down in the substation down in the basement um then uh yeah. it depends on all the other loads uh that are on in the building.

You'll get you know some sort of voltage drop there. So I don't know, is that good? I don't know. Industrial electricians with building experience down below sounds all right to me though. and it does have that non- cont voltage tester and it it it works Okay, like you know it's good enough.

but but really? I like if I was an electrician I wouldn't have this because I don't want to rely on something that has two um AAA batteries in it. You know that's battery powered I would want one of those smart passive ones. So anyway, let's take a look inside. So two AAA batteries.

It's interesting that they they looks like they got a separate mounting plate for the sockets at the back with four screws in there and wires going over. That makes sense because of course you've got to sell this into many different countries. and I don't know how many does anyone know I know off the top of my head how many different types of PowerPoint adapters there are, so have a squee down here. They got some celastic down there that's not too shabby and we have been blobbed there.

So there you go. There's a chip on board and just the blob on top. so unfortunately we don't know what micro that is at all. Maybe you could tell from the pin out cuz obviously.

um, the footprint here is designed for either a bare dye on there, a chip on board as they call it cob and then they just Bond the wires over or it's designed for a Qfp package like that. There you go. So they got some uh, test points up there. VPP There you go.

pick maybe I don't know? no idea. um and so yeah, obviously they're the programming uh, pins. and they would. They'd have a pogo thing at the factory to program that.

and what's an ET 6621? It's upside down. all the electrons are going to fall out there. you go, that's an Ech. um LCD controller.

Nothing fancy going on there. It's got 32 By4 bits of ram there. and yeah, that's just driving the LCD So obviously, um, they chose a micro that didn't have any uh LCD driver in it. This has quite a few segments there.

In fact, you can see that you get it at the right angle. You can see all the different off uh segments, but you know it's got two three-digit uh displays plus all the annunciators and uh, stuff like that. so you know, got some requirements there. Okay, so what else have we got going on here? I May have to actually rip all this off if I want try and reverse it somehow, but got a whole bunch of 1206 resistors here.

so these days the only reason you're pretty much the only reason you use 12 larger 126 packages like this: if you wanted higher power dissipation and or voltage uh, compliance in the voltage rating on them. Anyway, so it looks like this is we're being mooned here. This is the switch that would be the Yep this the Rcd test, uh switch there. and as I said, all they're doing is whacking in a resistor there.

um in series. So basically they got a 10K resistor there. Uh, presumably the other end of that just goes down to earth. So from live to Earth, there's really not much else doing here at all.

We got four around here and um, just some miscellaneous stuff up here for the micro and some caps here, but you know there's not much going on. We got a Diod here. not sure what that's doing cuz I don't know where these traces are buggering off to. so I might have to get this out.

Anyway, there's our non- contct voltage detection strip. so they've got that entire strip along that top. Edge Like that is the antenna. effectively the antenna for picking up the Um electric field there and that lead wire going over there.

that's going over to the backlight for the LCD So let's see if there's anything on the other side, but I'm doubting it. Okay, let's get that out of there. And now, as you'd expect, got a giant ass backlight there. Got our LCD got a zebra strip and Bob's your uncle.

That's it. We just got one lead down there, but it looks of it and the power button is actually a soft button there. so it's um on the of course on the battery side of things, but this one over here had to be a big clunk in switch even though it's surface mount. uh jobby because that's directly on the mains basically so they g a bit of effort there for the backlight.

that's not too shabby at all to try and get an even backlight. shame it's such a piss poor um LCD but so yeah, they've got like a different color uh, filter in there basically for um to give that green indicator for correct and basically the orange um for everything else. And there you go. You can see that you can see the filters inside there.

You can see most of it's orange, but there is a green part to that as well. So that's just, um, like filter masking so to speak inside the LCD So the word correct is across there and that's how that one can. sharp green? Neat huh? But um, yeah, you can get your LCD manufacturers to do custom stuff like that for you. So although that kind of technique isn't hugely um, common the LCD manufacturers, they'll do that for you if you ask them.

No worries whatsoever. There we go, we can see all our segments. isn't that neat. So that's the bottom side of the board I guess.

And and the top side here is so where is like traces like that buggering off to like clearance? much? Let's get this hot snot off so that we can see a bit better. Maybe Trace out. A couple of things All right. I've done a quick reverse engineering the board here.

not 100% but good enough for Australia It'll give us a great idea of what they're actually doing here now. It wasn't particularly easy to find out what this IC here was, but I might do a second Channel video on that. Uh, so here's the top and the bottom here and I didn't have to, uh, remove any components to what's going on here now I Thought this was just a regular micro, but aha, it's not. It's actually.

well. here is the schematic: They actually use a Multimeter chipset and it's an S7500 here. and you might recognize this kind of arrangement because it's essentially a multimeter front end that's doing everything here. It's powered from 3vt batteries.

it's got the soft power button there, it's got a couple of uh transistors driving the backlight and the buzzer here. and it's got your sort of like traditional com terminal on your multimeter chipset here, and then your input voltage divider here which goes into your various usual multimeter architecture uh, multiplexes and stuff like that and your ADC Curiously, this one does actually have an in internal LCD driver, but it's actually using that um, external uh chip because it's got Drive sort of like custom segments or something I don't know what's going on there and your Rcd test up here is exactly oh I forgot to put the values on there. they're 1K 6 each. Um, so yeah.

just let's get the confuser out. So we got 240 volts divided by 4 1.6 K that's 6400 ohm skis. Um, we're getting 37 and5 milliamps and that's basically what you want cuz you're a regular Rcds trip at nominal 30 milliamps. Um, so yeah, that do the business and they've got a reverse protection diode across there like that, um to protect the and that's just an LED um on the front which lights up um and Bob's your uncle.

but yeah, um, you've got your input uh, protection resistor here. two 5 Meg resistors in series. And of course I mentioned you put multiple resistors in series to get the Uh clearance and the voltage required. so they've done that three times here.

They're actually 4.99 Meg but you know, five, five M Good enough for Australia And they've got a 10K down here on the Earth and the Earth is directly connected through to the com terminal here, and the neutral is in the middle, so that's interesting. So obviously in a correct configuration, when the active neutral and Earth is plugged in correctly, they've calibrated the software so that it measures whatever it measures on here. We're not going to go into details of exactly how it measures that with the multimeter chipet, it doesn't matter for the purposes of this video. the fact that yeah, it makes sense to use a Multimeter chipset here.

and what about the non- contct voltage testing? Well, I haven't done that here, but that's actually it's going. Go take a look at the data sheet over here. It's the Sdic SD 7500 and it's an auto ranging six Channel multimeter system on chip. So it's got all the LCD drivers so it can actually drive.

You know, one of those little cheapy $2 meters. You could actually use a chipset like this to actually do it. and it's only available in the one footprint here, but obviously you can get it as a be dye uh from the company. In fact, can we go right down the bottom? can you? They don't mention be Dy But pretty much any manufacturer will sell you a bear die if you ask them and you order sufficient volume.

it makes sense to use a Multimeter chipset. All the functionalities, uh, building there. Why not? Anyway, we won't go into the internals here. but so suffice it to say that the Com terminal which is connected through to Earth here.

that is Uh, the Com terminal here. and the battery connects to Vdd and Vsss. So the battery as you saw on the schematic. So this is the ground.

This is not Earth This is the internal circuit. Uh, ground. and that's connected to the negative of the battery. but that's different from the com.

They're not actually electrically tied together, but that's common in multimeters, huh? Common? Get it here a week. but yeah, it's got all the stuff required for your regular multimeter here. and it's got an internal voltage reference of course. Um, and it's got an 8bit risk.

Um MCU What actual risk? Micro that is it. Maybe its its own flavor, but here is a typical application circuit. Here this would be your multimeter. So this is the common of your multimeter.

This is your regular Volts Amps Jack here and here's your you know when obviously not using the current input here, but you can see that the common terminal is connected to the pin 12 the com of the Uh chip over here, which is different to the Vdd and Vsss see how it's got uh, like a circuit ground over here is not. And if you measure, go and check out your multimeter and look at other multimedia videos I've done. The com is almost never connected to the VSS uh battery over here they're different and you can see that it's got a non- contct voltage tester capability built in. So obviously, um, you know it's got a two transistor.

uh, clamp over here. Not sure if that's what these extra two transistors here doing I didn't show those on my circuit, but that's the uh backlight and the buzzer uh driver here. So we got an extra two transistors here. the non- contct testers up the top there.

it's got one Meg So there's obviously like a trace going down like it does here on the yeah, it goes down here somewhere. Didn't bother to trace that out, but that actually connects into Pin 8 here. And we do actually have already using Pin8 here for our um, basically this this connection here. this voltage tap between the neutral and Earth here.

so I can detect you know, a broken Earth or whatever. So this node here you can call it is also connected to the non-c contct voltage uh terminal here. So that's what they just use Pin 8 here. So there you go.

like it's It's incredibly simple. It's just like a a regular multimeter uh chipset. It's it's smart. Um, if you want to make a device like this like a smart device like this, Yeah, it makes sense.

Multimeter chips is are already designed for this sort of stuff. You've already got your non contact voltage thing. You get that for free. That's why they included it, even though it's a bit of a pointless wanky feature.

But it's free, so why not include it and that buzzer terminal? They do actually use Pin 22 down here on the Uh design for the Uh buzzer. and then you've just got that those programming pins which we uh saw before on those pads there. Hence that's the VPP and these ones over here. And they must have another pad for ground and stuff like that before they s it probably underneath the battery.

uh, terminal there. so you know Pogo pins. Uh, to program this chip? Uh, once they've sold it it, you wouldn't buy it from the manufacturer you might buy D Be die pre-programmed Maybe. But given that, um, the pads are on here, it's It's more likely that they're just buying it blank.

They're whacking on the board and then they program it later. And then of course you can updgrade the uh, firmware at the production uh stage. It's not for user updating of course, but uh, certainly. if you want to do any bug fixes, you can do that later.

So there you go. Just a multimeter chipset. Um, curiously, they didn't use the internal LCD driver even though it's got it. Um, so some little small Quirk meant they couldn't use it for some reason.

Perhaps there you go. I Was expecting just a regular micro, but no. Now now that I think about it. Yeah, it does make sense to use a Multimeter chipset in this application.

So there you go. Hope you found that interesting. If you did, please give it a big thumbs up. And as always, discuss down below: catch you next time.