EEVblog 1489 - Mystery Teardown! 

Thumbs up this video and this pinned comment if you want to see a countdown timer refit project!

Finally, a proper case for a Raspberry Pi! :D

The principle of this type of protection is that they assume the thing will fill with gas and ignite, and the enclosure must not allow any flame to escape. (During the approvals process, they test this using either hydrogen or acetylene + oxygen, with expensive gas analysers to get an accurate mix to meet the standards) This is why it has a long, tight-fitting flange on the main enclosure joint. The terminal area has less stringent requirements, so no flange, but also no active components. I think the external glands ( called line bushings) specced for use with these are designed to be gas-tight and not allow gas to go through the cable, hence the lack of per-core sealing here - they typically have a bulkhead filled with epoxy, with the wire stripped bare where it passes through the resin. This is not the same thing as intrinsic safety - with IS, the protection is provided by limiting voltages and currents by design, whearas explosion proof (Ex-D and Ex-E from my hazy memory) is used where this is not practical due to power requirements. The soldered fuse is not uncommon - a major part of design for Ex approvals is not so much designing it to be safe, but designing it to be easy to prove it's safe. It is standard practice to include fuses, zeners etc. that have no chance of ever acting in normal or even fault conditions, just to make it easy to compartmentalise parts of the circuit to make it easier to evaluate for approvals. Including a fuse is a simple & cheap way to prove that the current can never exceed a certain amount under any circumstance - the standards define how much current can pass a fuse of a particular rating, the number 1.7x rings a vague bell. It also reduces the risk that some idiot replaces the fuse with the wrong value ( "less danger of it blowing guv....").

I design industrial explosionproof electrical systems that something like this would be used in. Aside from the obvious heavy duty nature, there is a whole field of study you could jump into regarding flame paths through all the seals, gaps, conduit entries, etc. That is a HIGHLY engineered piece of equipment and probably costs as much as a house! Good on ya for getting one in your hands!

I was an engineer at Net Safety for over 10 years (a Canadian company in fact) - it's a blast from the past seeing the "Banshee" here! I worked on the electronics and firmware for every gas detector we designed from 2004-2015 except, ironically, this one - it was a rebranded product. We all had the same reaction to the looks!

You also need to put an eccentric motor vibrator inside that triggers when the countdown reaches 5 seconds or thereabouts, so as to intensify the effect.

"It's not a bomb it's a clock!" (also, Dave that would make the IDEAL kitchen timer for the Mrs...) 🙂

This construction brings to mind the commercial nuclear plant radiation sensors mounted within the concrete reactor containment that had to survive a LOCA (Loss of Coolant Accident). The sensors needed to survive not only the pressure pulse of the explosive release of steam, but also the more troublesome thermal heat pulse, not to mention the radiation pulse it was intended to measure. Those same standards applied to everything within the containment connecting to the sensor, including conduits, cabling and most importantly the connectors. The main approach was to use lots of secret-sauce epoxy everywhere, so the housings themselves didn't need to be built so robust, which particularly mattered for the sensor, as excess material affected its sensitivity, and a large neutron release could make the housing itself radioactive. Even the heat-shrink enclosing the connectors was beyond special, where a 10 cm length would cost $200. The coax was an entirely different story, as no manufacturer was willing to certify their coax for LOCA. So we had to do the certification ourselves. While we had access to a physical LOCA simulator for temperature and pressure (which sounded like a bomb going off), we did not have one for radiation. The highest radiation flux we could find was behind the beamstop of a small linear accelerator, where we made a small closet and hung coils of the coax candidates, to be pulled out and tested/characterized every month or so, along with measuring the total radiation dose. To keep the cabling to a minimum, we sent 2-4 KV down the coax, with the radiation level encoded on the return. During the LOCA event, the pressure and temperature pulses would significantly change the capacitance of the coax, an effect the overall system had to both survive and account for with great precision. The coax runs could be up to 1 km in length, to get the measuring instrument far enough away from the containment for it to continue to function through the event.

Worked on 'explosion proof' fans and such in the Navy. They aren't completely 'gas tight', but the idea is that any explosion inside won't ignite the atmosphere around them. So for example, submarine battery fans (H2 hazard) had to have very close tolerance fits. H2 might actually get inside, but if it ignites the flame can't 'blow out' through any of the tiny cracks/ crevices. Sort of like how a steel screen placed over a bunsen burner, the flame won't go up through even though hot gases flow up through the screen. And of course the casing is strong enough to not rupture if the inside is filled with the 'perfect' mixture of explosive gas/air. So that interface cable might let gas seep along it between all the individual conductors, but that's fine.

You've got to modify the display to count down... maybe it can do blanking too so it flashes when it gets to about 10 seconds or something too.

At 16:00 you mention seeing the home-made optio-isolators before, but didn't remember where. They were in the electric fence power supply you cracked open a few years ago.

I swear this looks like the training drone that Luke skywalker and obi wan kenobi use in Star Wars Episode 4: A New Hope

Hello :) In the factory where I work, there is a unit where we produce ethyl alcohol. We use Ɛx rated appliances there. Many of them have similar soldered fuses. When I asked one of the manufacturers why they were like that, they told me that it was a requirement of the insurance companies and a policy of our group as a customer. The idea is that in the event that this fuse burns out, the device should not be repaired, but replaced with another one. It's simply not worth the risk of putting an appliance that has had a technical problem in front of an explosion that will surely cause massive damage and kill people.

Please do! Replace those sensors with red LEDs that light up when "armed". It would be nice if it had an audible hum too.

Probes into the sensor heads are there to have the heater blocks screwed in instead of the blank probe, to heat the actual sensor itself in use in icing conditions. Self cleaning probably uses those probes, and then a separate port into the case that provides the air pressure for cleaning, via stainless steel pipes and a spiral tube that connects the ports to the top. That is why there are 2 recesses in the probe, one for the cleaner, not fitted and drilled to spec, or the heater, fitted to all but in temperate use only the dummy heater block.

Needs a motion sensor so it starts the countdown when you pick it up. Then just leave it around the lab until someone picks it up for a closer look, “uh-oh, now you’re bu**ered!”. Then some secret way of manipulating it so it stops. Perhaps a certain number of deceleration events by smacking it on the table in various orientations.

Ya need to have a big motor and weight in there, so when the counter reaches 0, it vibrates like mad, dancing across the floor, then stops, and a little voice says "bang."

Make the count down timer light up and start counting when touched or moved. Just think the fun you could have.

Yes you HAVE to make that display into a countdown timer, complete with piezo speaker that makes the classic "pip - pip - pip" sound that all bombs make in the movies/TV shows like MacGyver :) Perhaps you could even get pretty cluey and when it reaches 2 minutes left, include a capacitor charging sound (i.e. detonation/firing circuits charging up!) Yes it does look like a WWII sea mine!

Hazy memory but I did a bit of Exd and Exe design for UK offshore back in the day (80's/90's), so this unit is Exd meaning it's explosion proof, i.e. Any major problems on the inside won't propogate outside. The cable glanding and the ultrasonic sensors, i.e. Anything that connects from the internal space to the external world has to be Exd rated. There were some types of cable entries/glands that had to be packed with an epoxy type stuff. It's all about flame paths. If I remember correctly, you had to declare and submit a BOM and layout drg for the internals in order to comply with the Baseefa/ATEX Exd rating before use. Once done, you couldn't drill any holes or strictly speaking change any internal parts. Exe (I.S. intrinsically safe) was different, that was all about limiting voltages and currents via certified interface modules including zener barriers, galvanic isolators etc. I did more design on the I.S. side. I remember designing and getting approval for a large Exe Lcd display and during the cert process being limited to the amount of total capacitance on my Pcb, the distance between components etc etc. With Exd, you are given a lot more lateral. Dave's unit it would have been one expensive puppy back in the day........! Ian

Totally looks like something out of Tales from the Loop. I Want one.

Banshee 343? Is that a Halo reference? 343 Industries is apparently named after the character 343 Guilty Spark, which would be fitting for an explosion detector, and it even looks a bit like him.... the font even looks like the 343 Industries logo

You have the explosion proof issue backwards (I have sold industrial electrical equipment for over 40 years and have sold thousands of EX rates pieces of equipment).. They are designed so that if there is a failure inside and ignites the gas inside the device the flames and or explosion is contained and wont ignite anything outside the device.. If there is a breather it will have a very fine metal wool inside to prevent flame propagation (If they made all their own components they could have hid the breather in the cable connector). The inside volume is usually very small to limit the volume of flammable gas.. Less gas, less internal pressure if there is a fire or explosion inside. The volume of this device is huge thus the extremely heavy walls.

You should totally make a countdown for that! Maybe also have it make whirl click and beep sounds as it counts down.

This is what you get when you tell an engineer their is no budget. Just beautiful.

Awww, I’m so disappointed Dave..! I was fully expecting to see a couple of Plutonium hemispheres inside there surrounded by a shaped explosive lens, with at least a 25 kilo-tonne yield…! 😉😁😂

A few years back I built clock which would read the correct time except that the seconds would count down. I started making a case for it from PVC pipes but figured it little might cause some panic so I never finished it. But maybe sounds like a good project for your case.

"Internal heating" - 160W power consumption They play the same game with security cameras.

Funny how a doomsday preventing device looks so much like a Futurama doomsday device.

"Banshee 343" - Is the name of this a video game reference? The Banshee is a vehicle in Halo, and 343 is "343 Guilty Spark" from Halo. Halo series is now looked after by 343 industries.

That tiny board might be a hall sensor to allow external test activation with a magnet

Maybe the to220 are used as heaters

You should paint the case yellow with black diagonal warning stripes around the midsection.

According to the movie Hot Fuzz, that's a sea mine.

thank you! This is adorable, this thing has been assembled by hand by skillful workers. I would retro-engeneer the counter and use it as a time display, add a MP3 player circuit in there and use it to listen to music in the bus :p

My first thought seeing a sphere with sensor pods... *'Oh sh~~ he's got a nuclear reactor!'* I do like the over-built industrial containment aesthetic.

"Banshee 343" sounds like folks from Halo designed the thing At first I had the same thought of being something used underwater...maybe sonar or underwater microphone for example. And you can go further than just a clock. You know you can!

Please do the mini project Dave... Thanx 10/10

so... it is a super deluxe version of those 'hising sound' ultra sonic mic with amplifier using in detect air condition and gas leak? totally agree that thing won't pass airport custom for sure🤣

I can see this thing be a perfect empty shell for either a movie prop or a "defuse the bomb" kind of gimmick that can be used in airsoft games or an escape room. You could put some RGB LEDs in the transducers together with a speaker to signal the bomb has detonated and the "defusing" team has lost. The IR can be used with a simple TV remote for code input to defuse it.

As far as the heater, look at the part you referred to as a heat sink. Loved the video

If you think about it, in a weird way it actually is pretty cool and beautiful...all the machining, the paint job, etc

11:30 that put me right on the edge, wow. I thought i was watching THE HURT LOCKER...im even shaking, i thought some bars of pressure about to go 💥💥🎆🕳️

There are some much less beautiful sensors equipped with IIoT, which also detect the ultrasonic sound of water pipes leaking. To increase the precision of the detection, they are used in large numbers in a mesh network.

The pcb for the countdouwn should also have a speaker that does ‘tick, tick…’, or possibly a loud relay.

Turn it into an Alarm Clock!

Someone has probably mentioned it already but on page 22 of the manual, the empty space, between the sensor houses, is described as "pump compartment". Also, on page 46, an "H2S pump" is listed as a spare part.

Looks like it has been dropped at some point. The posts holding the internal PCBs had snapped off which is why there were so many crinkle washers loose inside. Along with a countdown timer you need to add some accessible wires that can be cut to stop the countdown (but which colour should be cut? red? blue? green?) and if the wrong one gets cut it lights a small pyro to scare the bejesus out of you.

You will probably find the TO220 devices on the heatsink are the heater, for preventing icing in cold climates. Fuse is soldered in so people can't replace it with a wrong item reason is:. That opto isolated area is all about limited energy so there's not enough power there to generate a spark at the microphones in any possible conditions. The power will get across there via that fuse then there will be zeners to limit voltage and blow the fuse. There is also a mandated clearance distance around that intrinsically safe circuit, which is why the homebrew optocouplers exist.

Perfect sealing is not important. What is is preventing any flames or sparks from getting out. There is no gunk inside the cable because the cable is effectively acting like a spark/flame suppressor, wicking the heat out of whatever gasses may be attempting to make their way through long before they have a chance to ignite anything.

Make a widow for a solar panel to power battery then to the display? Thermometer with temp display? Time capsule with count down till open display? Or days since opened display?

5:26 that kind of looks like a burst disc, which is a telltale for pressure waves in air. they can be calibrated to burst at specific pressures to indicate how strong a blast is (in terms of the pressure wave). i've never seen a burst disc hidden behind a sealed panel though. that panel over it almost looks like a GPS antenna, but its facing the wrong way lol

Hi Dave , The Key to EP is not to pressure seal completely, but let the hot gases cool as they leak out so they can not ignite the atmosphere outside.

Yoooo! That 343 logo uses the same font as the 343 Industries logo for the devs that do Halo. And Banshee is a Halo vehicle lol

This Is an incredible find. I have only seen one similar device. That was in the early eighties. I had a neighbor who was a top notch nuclear physicist. He took me on a tour of Brookhaven lab ( and his experiments in the early 70's. This instrument is a result of the experimentation of that era.) Thank you for showing the basic tech. You should look back to the origins. I worked in the intelligence us Navy, in the 80's and this type of system was just being instrumented.

Yes please do the counter!! You could also add a little smoke machine so it starts to smoke when it gets to zero

At first I thought it was an airspace gyroscope. Anyway, I love expensive machinery teardowns, especially mil-spec items. Medical equipment is also high quality, way above consumer grade

I have been waiting for this!!

"You wouldn't get it through airport security" - I'll say! It looks like an anti-ship mine.

This looks like a spare part for a TACHIKOMA.

It's surprising to me that there's so much empty space inside. I would have thought that having as little room for gases to accumulate would be a good thing.

I have no idea what any of this stuff means. But it looks cool.

Maybe swap the ceramic sensors with flashing LEDs on the countdown timer as well. lol

Dude. Your something else. Countdown clock to display for fun making kids think it’s a 💥. ;-). Large vibrating motor for shits n giggles

MAKE IT! JOIN THE MAKERS! Do it Dave! Do it!

Looks like a Submarine mine or sensor! 😂

I want one of those. Have no clue what I would do with it, but I want one.

YOU COULD PUT A RADIATION STICKER ON IT AND PUT IT OUT SIDE PARLEMENT. AND THEN WAIT FOR SECURITY TO SEE IT THEN RING IT WITH YOUR PHONE TO ACRAVATE THE TIMER. AND FILL IT WITH A LOUD TICKING SOUND AS IT COUNTS DOWN. AND WHEN THE COUNTER GETS TO ZERO YOU COULD GET IT TO SET OFF STROBE LIGHTS AND A HI PITCHED SONIC SOUND THAT MAKES EVERY ONE POO THY PANTS LOL. 😂😂🤣🤣😂😂🤣🤣😭😭😭😭😭😭😭

Everlasting Gobstopper

I would turn it into a lamp- yank out the guts and the ultrasonic sensor bits, have LEDs with frosted covers shining out of the little black rings on the end of each protrusion, maybe a clock display on the digital readout thingy. Bonus points for pulsating leds that brighten up and dim down in sequence...

Get Dankpods on the phone STAT.... you must make that thing into the ultimate MP3 player. Put a headphone jack in each of the 4 sensor housings so 4 can listen to the giant music grenade together. Make the sensor housings into knobs that rotate around the jack for individual volume controls.

there is supposed to be a pressure release valve if that thing is pressurised. Its the law, ... GAS SAFE....corgi is old news

It reminds me a mini nuclear bomb.

Gas leak detector,looks like a mini nuclear reactor to me

This totally needs some sort of IOT connection, perhaps to set the timer, to start the countdown and a webcam or lighting, all linked to the EEVblog website 🙂

I love how excited he sounds through the whole video.

Countdown timer and a Nuclear symbol = "The Toy Of Doom!" YES.......

TURN IT INTO A COVID 19 DETECTOR LOL

At first glance I was reminded of the on board fire extinguisher pods on USARMY Sikorsky UH60 Blackhawk Helicopters. I was looking for the firing squib ports on that bit of kit there. Thanks Dave !

I'd be keen to see multiple videos related to the "build a counter circuit" idea. Reverse-engineering in one, block-diagram design of the replacement in another, then schematic design, followed by PCB design and then final finished project presentation to round out a cool 5! :)

When I first saw it I thought it was a planetarium projector head.

This look like nuclear boom 😆🤣

I think you need to put the timer onto this with your kids so they can take it to school for show and tell to show the other kids what they and dad made on the weekend.

You mentioning maybe adding a countdown timer to that thing reminded me of an old series. In the UK, Roger Cook was an investigative journo, and used to do all kinds of bizarre "stunts" in his series. The "nuke in a suitcase" episode is worth checking out. lol The Cook Report - Dirty Bomb S08E01

Looking like a nice atomic clock! haha

How is it not a single sifi prop-master has ever used one of these in a production, the right paint plus a few blinknights and you've got a 'quantum singularity inversion mine'.

Isn’t the 343 banshee a node to halo?

I wonder if these are used on submarines where air quality and contamination detection is a major thing.

"The BOMB, Dave. The hydrogen bomb!" Hot damn, the alumin(i)um alone in this thing would fetch a good buck at a scrapyard! :) I'm impressed by how it's designed and made, it's EXTREMELY clean and durable! None of that cheap chinesium rubbish. Cool optocouplers here. I wonder what's the type of receiver, is it a phototransistor, photodiode or LDR. Speaking of which, VTL5C3 comes to my mind and I'll be doing my own experiments with a resistive optocoupler for VCAs with optical control elements for compressors, limiters, tremolo circuits etc. stuff.

The casing looks like something that could be repurposed into a high pressure chemical reactor!

Stupid laugh🤣🤣🤣🤣

recreate one of Professor Farnsworth Doomsday Device from futurama

I think a countdown timer project is a good one

And just like the Death Star, it has a convenient, tiny path of ingress through the cabling to all the sensitive bits inside.

6:24 mini XLR connector

It’s a submarine mine

Can you solder fuses like that? i have never seen that before and assume they are not rated for reflow surprised to see that in a product like this

It remembers me of those Ghost in the Shell robots called Tachikoma. Right?

Maximum voltage 30v, maximum current 5A, maximum power....160W. How does that work XD?

This must be turned into Darkstar / Starship Troopers (book) grade "talking bomb": "I'm tactical thermonuclear bomb, I will detonate in 5... 4... 3... 2... 1... Let be a light..."