This rather chunky device is a meanwhile surge protection device. It's designed to be used with mean mail LED power supplies in signage so that if there's a lightning Striker that voltage transients in the vicinity, it will clamp those spikes. And it's quite interesting that the data sheet has a full schematic of the inside of this, which is maybe just as well because if I pop the lid off this, it doesn't reveal an awful lot. If I can get lit off, it's very, very tightly snapped in.

but it reveals that uh, the interior of this that is so tight. Yeah, that is very tight. yeah, is potted in resin. This is not good, but I'm going to see if I can break into that I don't really have the tools needed to do a super deep investigation, but I'd like to break into and roughly see if I can find much but there are two LEDs a green one here of the green one here used for a fault diagnostic purposes.

If they're both lit, it means it's working I think and if any of them goes out, it means that you have to change the unit. but I shall, uh, open this I'll take it into work I'll open it and we'll see what's inside one moment, please. Well that was not easy but I did manage to break my way into the unit and made a huge mess the process. It had a layer of resin approximately thickness of this pen which is about 10 millimeter 3 8 of an inch and below that was a very coarse almost like quartz sand.

very Very white and coarse and that's Blended There's some of it left where it had been permeated into the resin and the construction of the unit was such that they had this plastic housing that they had placed into the empty case and then they'd sat these in and each of these is a metal oxide Barista with a thermal fuse actually integrated into the same package. More on that later. So they dropped these in like this and they have three wires coming out and the construction was such that the wires come in to the cage from the side. Let me Zoom down this a little bit.

The wires come in from the side. There was no circuit board, they were terminated and tinned and then this assembly here literally had the wires bent over onto these bar these uh, large wires coming in. It's very robust, no circuit board which would be a weakness in this case. Uh, so a good solid electrical connections and the LED on each side simply has a fairly high power one watt 39 K resistor, A1n4007 Diode and a traditional green Gallium phosphide.

LED and that also there's no circuit board. They've literally pressed the LED into the casing and then just taking the wires over with a bit of sleeving and Tack them onto the relevant connections. Let's take a closer look at one of these. I Also got a little extra bit of video work which is super interesting.

Let's make sure this isn't thick ass. So here is the complete module and it's a distinct hump on one side which contains the thermal fuse. The thermal fuse is a ceramic package with two solid wires going in uh and a bit of I'll show you a representation of that. then I'll show you tripping because we did that.

and but this is a the metal Ox of roosters put in with the thermal fuse connected onto its Tab And then the whole lot is pointed this very hard white resin. Um, not much else to say in that. Let me show you a representation of the thermal fuse. So the thermal fuse is a ceramic package.

It has very stiff wires, everything's very heavy. I mean seriously, this is a proper industrial component, but then it's got a sort of low melting point alloy like solder bridging from side to side and there was a sort of crystalline sub substance surrounding that. and I thought maybe that's going to absorb the soda? Well no, it turns out it was flux and when I heated this up, um, the flux melted and the soda just sucked onto the sides, Let me show you what that looked like and then try while look at the camera to actually one moment please put that on there. oh it is.

It's all just fizzling in. it's all that's kind of broken I didn't realize that was Liquid is that flux? Then it's basically oh, it has. It's just gone right. And oh, that was useful.

That was worth doing so. Now we've seen that going. Let's take a look at the schematic. unfortunately.

Meanwhile, being a professional company, I mean they're really one of the highest profile names and power supplies. And for that reason, this this surge suppressor I like rated very, very highly. It's got some more symbols in it. It's these are Metallics, Everesters and these are thermal fuses.

The Znr Uh is a kind of old-fashioned I think it's Panasonic about that zinc oxide non-linear resistor otherwise known as Movs metal oxide resistors Um, or Vdrs voltage dependent resistors. So each of those packages there has the thermal fuse and the metal oxide Barista and there's one basically bridging from neutral to live neutral to Earth and Life to Earth. So they're all avenues are covered, so to speak for the transients: the LED indicator based on the 1n4007 Diode, the Gallium Phosphate green LED that's kind of important and the 39K resistor the Gallium Phosphide LEDs are the sort of dull old-fashioned green LEDs The main advantage of Organium nitride is that gallium nitride that the reverse leakage. Well, they're unreliable basically, and the reverse leakage from this diode might not be enough to actually protect the gallium nitride.

LED They hate being reverse biased and they potentially fail. So they've used an old-fashioned uh, Gallium Phosphide green LED simply for reliability and the way they've got it configured is: if this fuse blows uh, then that will break the current path between the neutron. live through that Led and that Led will go out. And the diagnostics for this indication in this unit are: Check if both screen LEDs are lit.

If they're not lit or just one of them has gone out, then part your protection is failed, one of the thermal fuses is gone, and it means it's time to replace the unit. This other LED down here is effectively in series with this thermal fuse from live and uh, this thermal fuse from the neutral. So that either of these thermal fuses goes, this Led will go out. so that's those two.

LEDs Cover Uh, all three of the fuses. The modules. The little black modules these have taxed on them. It's very light colored text.

so I wrote it down here. it's set. possibly brand TF Mov 25d471 That probably means thermal fuse metal oxide Varista 25 millimeter diameter disc and 471 means four seven and one is a multiplier. So that's 470 volt, which is the point.

It will start conducting slightly. It also says Mcov not quite sure that means 300 volts Ac. That's its rated continuous voltage without actually starting to shunt. Um, and that is it.

I Am very, very impressed by that unit. The internal construction was extremely good. That's pretty much what I would expect of Um. Meanwhile, product.

So big chunky components, The equivalent generic company component unit would have much smaller metal octavisters and the resistor here would have been much smaller. The LED would have drawn just glued faintly and and also this resistor would have been under stress. This is I'm talking about other people's products here, but not. Meanwhile, the meanwhile unit is one that's not just for protecting their power supplies into LED drivers.

That would make a very useful addition to protecting stuff like HVAC equipment or other electronically controlled equipment that you wanted that layer of extra protection for in a nice robust, waterproof package. Top marks to Meanwhile, that's an excellent unit.