Hi got a real interesting bit of kit for teardown for you today. This is a Schaffner haha made in Switzerland Hi to all my Swiss viewers, the NSG 200 Mains interference simulation system and I scored this from the that big dumpster that was outside of a in company who still shall remain nameless even though this one actually has Alcatel Australia part numbers on it No, it wasn't Alcatel and someone called these standard telephoning cables proprietary limited. Um, no, it wasn't them either. So I'm not sure what the deal is there.

So what this bit of kit is for is for like EMC and compliance testing houses that actually test your products for various standards and susceptibility and things like that. And depending on the type of product you may have - like a Mains Power product, you may have to test it for various mains, disturbances, dropouts like lightning strikes on the mains and things like that, surges and bursts and other motors, switching on on the mains or relays, clicking and you know that loads switching off and on all these little transients and pulses on the mains. If you want to ensure that your product survives these, you need one of these things and generally you'll only find these in that test houses. You might find them inside some you know, companies developing mains power products and things like that.

but it really is a very specialized bit of kit and it is actually a mainframe based system. It's the NSG 200 mainframe which is just this main power supply over here. and then you can get all these different plug-in modules and we should be able to take this one out. This is the MSG Triple 2a, but you can get like half a dozen different modules for this system that simulate things like mains dropout for example: DC Drop out if you've got a DC powered product.

this one which is the Fast Pulse Interference simulator. This one actually tests 100 nanosecond pulses with a rise time of either 5 or 10 nanoseconds here. So really fast pulses design to simulate things like you know, loads switching off and on very fast on the mains that can, they'll elsewhere on the mains that can cause interference to your particular our product and this is this is its only job. It's only job is to generate these hundred nano second pulses at various amplitudes up to several kilovolts.

And there's a apparently a standard for this, the 45 1, 7 / 79 I don't know I can't really find any information on it I Mean maybe have gone into a more like a recent standard This, you know. this is a fairly old bit of kit, but this would still be used in test houses, no doubt. So in addition to the first simulation pulses, you can get other types of bursts and also high energy pulses up to you know, five kilovolts. You know things like that like real high energy pulses into the mains this one's just designed for I don't necessarily high energy but fast amplitude pulses from like five and tens of volts like 50 volts minimum.

I think up to what several kilovolts. so I have no idea if this thing works, but let's have a look. I actually want to turn it on before I take it apart just to see what the state of it is and on the back of it here, you can see that it all must connect internally. There must be like, you know, like a contacts inside or something like that.

I'd be surprised if it's a cable based system going over, probably some contact based system and there's the details for those playing along home. We've got the mains, just the standard mains input, but also for the test supply of the product that you're actually testing so we can plug. Let's just plug this one in first and see if it at least powers up. So I don't know why exactly a better kit like this will be thrown out there.

Ridiculously expensive specialized bits A kit. Maybe it's just obsolete. It doesn't suit the new standards anymore and they have no use for it. so let's power this on.

I don't know what? look Yay! Feel that haha. Pulse-amplitude sweet I can hear something going buzz so Oh pulse there we go and that'll go all the way with LBJ up to how many Kilovolts should be. A couple of kilovolts? Yep, Yep. 2.2 kilovolts we can go up to and we can.

Whoa There we go External Pulse: We can apply the pulse or we can feed in an external pulse from here. I Yeah I think they've tossed this out I think I'd be surprised if there's anything wrong with this actually. I You know confidence is high I Repeat Confidence is high. And sure enough, if we plug our 240 volts into the second test supply socket over there and we hit the big test supply button here.

Bingo! We got our 240 volts to here in the lab. Two hundred and forty seven volts. AC So we should be able to apply. Here's a little hundred volt pulse.

Boop-boop Of course we won't see anything on the multimeter. Looks like we gonna have to get the scope out and a high voltage probe. Just want to show you this. when I put it on that free running frequency here.

just listen to this. You can hear it. and then when I switch it over the point to FL You can hear like a relay switching in there. Neat huh? I Think that sound that actually sounds like a real eye switching.

Well, unfortunately, the magic smoke is escaped. Well, something wins. Snap, crackle, and pop. Damn it.

So oops. Yeah, something went horribly wrong here. It's a week later. two weeks later.

I Don't know. This thing actually panicked. It was releasing so much smoke. Panicked.

had to put it in a cardboard box to stop the smoke from setting off the fire alarm in the building here. and yeah, well. let's take a look inside and see what's wrong with it. I Think it was mostly coming from like this power supply section over here.

So yeah, let's get into it. and yep, even after that time, Good as predicted. a contact based system. Wow, that's a doozy the size of that.

but then again, this is like a high-energy thing so that's impressive. Wow oops I taking out the screws in there I Thought maybe this might slide out as well I didn't think it did, but dumb yeah. oops nut. that's just the loosey-goosey front panel and the back panel.

Surprise surprise. Which brand filter do Does a chef know bit of kit use well? Uses a chef and a filter of course. Top notch and they're serious about that earth into aren't they? Very nice. done right as you'd expect.

Whoa. Check this bad boy out. Oh let me show you the detail. This transformer is actually wound with solid copper like busbar things.

These aren't just like it's this and just regular like enamel coated pissant wire. These are like solid, thick as that. Like you cannot move though, cannot budge them. They are thick solid busbars.

That's incredible. I Just get the calipers on that. for those playing along at home, it's about 3.1 millimeters by two point, two millimeters thick. I Think we can see our problem.

You can just see the thickness of that. the busbar. I'm just gonna call them busbar windings cuz they're just absolutely enormous. But that is that where our smokers come from.

Look, it's stripped down there. It's got that telltale sign of of having dripped off. Well, you can just get a feeling for those windings. Unbelievable.

Yeah, that's that's where the magic smoke escape from. And not sure why or how that did it cuz it's not like we were loading the theme down. she's burn away. So yeah, it's it's not gonna be able to.

He's gonna fix something like this. You can see here that the well, it's I'm not going to call it the primary and the secondary because it's not because this doesn't look like it's doing a transformer operation. It looks like a huge choke. It's burnt that top bit and then drip down.

It's really strange, so maybe you know some like breakdown between one of the windings in there. perhaps? But geez. Now in terms of operation here, we've got 50 60 Hertz like tap I guess and 400 Hertz look at that. That's really interesting but I'm not sure how like it.

how it's like selects 400 Hertz or 50 60 Hertz There's no like selection for this this thing. There's no foot. well it's got 50 60 Hertz on the label here. but yeah like it's all hooked up.

so like guys. So I'm not sure what the deal is there but there's not much on the board at all. the mains input right here that just goes over to the switch on the front and then that's also routed to the board probably for some switching and then goes over to a terminal block here which then is going to bugger off which then comes just goes directly into these contacts here. So like this is not a transformer for the modules.

the modules basically I have their own 240 volts input so the modules will have their own local transformer to do whatever our power requirements that they have this block here which is a chef knife branded made in Switzerland or my Swiss viewers again it's like just a big potted monolithic block. I'm not sure if you can see that down there but that's an ITT cap. maybe West Germany Nice. East German Rubbish.

Now I Did finally find a schematic for this thing and as it turns out this giant transformer here is actually a 16 milli Henry common mode choke and this Schaffner RF 5 to 9 big Potter unit here is a massive filter and the board is just basically and some extra like filtering type stuff. but yeah it's not much to it at all. but this is an absolute beast. so I'm not sure what happened to like burn this common mode choke.

that's just nuts so that 100 Hertz 50, 60 Hertz labeling there which seems to label like each different like tap there so to speak. Um, that's a furphy because this is a common mode choke it. There's no switching or anything based on frequency. it's just there.

So yeah, that label ends a bit. Don't know why they did that. No. Inside the injection module isn't that sweet.

so we've got a big-ass contacts coming in here. I Love that that's absolutely brewing, but that is really quite neat. There's not. you know, a lot of space in there, but that's very neatly laid out.

We've got the the control side of it all over here, which of course because it's got to do the display. it's measuring I look and chips almost falling out. Check that out. I've never seen that and chippies almost falling out.

That is hilarious. I'm not saying that, aliens, but it's aliens. It's nothing too exciting on this board over here, but I like their little nice little regulation local regulation block down there. well it seems look that's very nice at and they've got seal pads on each one.

It ties into the show Z down there, Beautiful. And of course we've got a mains transformer here. 240 volts just comes in on the bottom side here. Wow Oh, that's an elk.

oh it's an elk. Oh Elko Fanboys it's upside down so all the electrons are gonna fall out. but ah I See many elk? O's And what's interesting about the rest of it is it's all a lot like. you know, 4000 series stuff.

No this. TTL Rubbish. And the only microcontroller you can see in there is for the display panel board where they've rolled their own display panel board. It's got its own little trimmer for calibration and everything else.

So let's say they've actually are designed that for maybe you know, a few different products. Let's go decimal point near Ninety Nine Point Nine Nine Point Nine Nine. so you know that's really neat. It's probably used in several different chef No designs I'd be willing to bet wires just soldered onto the cord eggs of the lid.

They're pretty how you're doing, but all the interesting stuff is over on this injection. PCB over here. I'll call it for want of a better name because that's really what it's doing. Check out the lead length they're getting on that pair resistor just flapping around in the breeze there.

Wow And they've put an insulator dust sleeve over the leg there as well. That one has the little alien crop circle in there and they just needed some extra inductance. I Guess yeah, these black jobs here. these are actually Keiko relays I Don't know those offhand, but I'm they're huge beasts.

Look at that. we might actually be able to. Can we just like pry it off there? Maybe. Yep.

I Got him shake that out. Isn't that beautiful? Near that lovely relay? you can see the contacts down in there like that and she pulls it in excite the coil and that's beautiful. That's actually a double pole, double throw contact. Neat.

Check this out. This is really interesting. We've got these mechanical buttons here of course which have these. just the mechanical indicator in there, just a little shutter which which just covers and uncovers that because this is like a real, you know, a high voltage high-power thing.

you want it physically decoupled. So here's the mechanical switch here. and it must have like a steel wire which goes around. There's Bend here and the actual switch is up on the PCB here.

So if I press that. that's where your 10 nanosecond pulse switches on the PCB Physically an electrically decoupled from the poor ass user pressing the button on the front. Aha. So maybe that's what our little crop circle is there.

Maybe that's a little bit of delay, but the problem with that theory is that the normally it's a hundred nanoseconds delay and you can switch in the 10 nanosecond. so it's not like you know that little coil was gonna add 90 nanoseconds in there. That's just not gonna happen. Anyway, it's switching in some sort of element which changes the pulse with this gigantic auras job.

Here is a huge high voltage read relay or just a yeah I high voltage relay. Sweet. Apart from that, there's not a huge amount extra, Not a little custom round transformer down there. A border board interconnect uses the good old fashioned dip a socket arrangement, but look, they got some copper tape on top of that.

The copper tape actually terminates on this side of the shield. They don't want anything coupling into that ribbon cable going between the logic and the pulse aboard. Obviously, they need that because you've got lots of fast high-voltage switching in here. So huge div t-they changing current over time.

You don't want that to couple into your ribbon cable and back into your logic circuitry just attached at the one point. On this side here I've basically just down to shows the earth a whole bunch of huge caps in there. There you go writer for six kilovolts. Yeah, another six kilovolt job and you've got these huge wire wound inductors here done by Schaffner made in Switzerland So some nude virgin in Switzerland I set there are well on these and heat shrunk them and they're on there with a nice big high voltage standoff.

Another one of these mysterious are potted filter blocks down there. You can see that just they go off because it's It's actually symmetrical on the line here and it goes off of the active and the neutral so to speak. But in terms of doing pulse injection like this, it's L1 and L2 they call it and all the connections just look brilliant. So they go over to either the banana jacks on the front or they go or they jump it over with this.

Brown Y Here over to the European test socket. Yeah, I'd say that's your main cap. they're storing the charge. That's a 4000 volt job' point o4 MFD none of this Milli Farad rubbish.

This is my Farad's so I'm 47 in 4,000 volts up. dude. math that's how much energy that they can dump into this thing in the whole rest of. its just a, you know, and just the mechanism to actually inject the pulse onto the mains.

So there's really not much else inside that. but it is fascinating and to look inside like a high-voltage test injection system like this. and it's really not something that you'd ordinarily get to have a look inside. As I said, this is a very specialized bit of kids, so that was a great fine to find in the dumpster.

And I think this injection module just works or interference simulator module likely works. Okay, it's just that. Yeah, we've had some sort of our winding failure in the common mode. choke on the input so you could potentially try and like take that apart and I don't know, try and repair it maybe.

But yeah, that's suddenly. Oh, the fair bit of smoke did escape from it, so it's not a happy little puppy. But anyway. I hope you found that interesting.

And if anyone's got access to a schematic for this, Armit please I'd love to six I Wasn't able to find one cuz that'll be fascinating just to see exactly how they implement this pulse injection onto the mains. And as always I hope you enjoyed that and if you did, please give it a big thumbs up and you can always discuss down below or over on the AV blog forum. Catch you next time.