Incredibly good Meanwell surge protection unit (with schematic)
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- เผยแพร่เมื่อ 25 ส.ค. 2024
- With Meanwell being one of the biggest players in the professional power supply industry, I had high expectations of this surge protection unit designed for use with LED drivers in outdoor signage, but also very suitable for many applications where you want to protect expensive electronic circuitry against rogue voltage transients caused by lightning strikes or electrical supply incidents.
The quality of this unit was an absolute treat. Robustly made with no PCB tracks or solder joints to fail. Instead the unit is composed of a housing for three separate thermally protected MOV modules, and the stout wires have been bent and soldered directly to the heavy duty incoming wires.
The unit has been soldered in situ and then filled with coarse white quartz-like sand and then a layer of resin added to reduce the risk of water ingress.
Fault indication is in the form of two traditional gallium phosphide green LEDs that will indicate when a thermal fuse has tripped. The thermal fuses are triggered when the MOVs (Metal Oxide Varistors) reach the end of their useful life and start passing enough current to get hot.
These modules are so rugged and affordable that they would be a good addition to protect HVAC, computer and industrial control systems. In some instances it could be useful as a whole-home protective device.
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This also keeps the channel independent of TH-cam's algorithm quirks, allowing it to be a bit more dangerous and naughty.
#ElectronicsCreators
This is the kind of robust simple design we need more of.
Apparently the brand name is also the underlying engineering and quality policy.
Thank you, Clive, for demonstrating the differences between good products and dangerous junk.
I worked for a major manufacturer of laser engraving machines, and we used exclusively MeanWell power supplies. We didn't see many failures.
Early in my career, I found a Meanwell supply powering part of a lab experiment and thought, "What a silly brand! What garbage is this?" Meanwell makes very robust devices from what I've seen. They definitely mean well.
It's a bit of an unfortunate name though - saying you "mean well" is like saying "well it's the thought that counts" or "at least you tried". It suggests you put in your best effort but didn't quite make the grade.
I believe MCOV = maximum continuous operating voltage. I’m a big fan of meanwell. We use their mains to 12V PSUs in various sizes in several of our products.Well made and electrically good designs, and towards the lower end cost-wise.
Heh, I guessed Max. COntinuous Voltage, but yours makes more sense.
Yep, that's what I came to say MCOV stood for, I was late to the video though.
Meanwell is amazing, I’ve been using their power supplies for home projects and large work projects for years and have never had one fail!
They are so good RS sell them under their own badge.
@@dogwalker666 But who knows if the RS labeled ones are as good as the ones that have the Mean Well sticker? Who knows, maybe it's the rejects that get the RS stamp?
@@andreasu.3546 No, The RS ones are prime quality, They only accept the best, I used to know the UK buying manager.
@dannybnapa High end industrial LED lights use Meanwell driver PSU's they have extreamly high M.T.B.
@@andreasu.3546 That's not the RS way.
Meanwell is a great company with excellent products...this device is no surprise to being well made!
we use the 120vac to 24vdc fully encapsulated for outdoor access control equipment
Used them for years for low voltage dc projects. Great stuff
Even when they screw up, you always know they Meanwell.😀
How did you make that comment 2 weeks ago when he only uploaded the video a few hours ago?
@@croakingembryo Some people get early access to videos before the general public because they are Patreon subscribers to this channel and early access to vids is a common perk for paying/donating to a channel.
That solder/flux trick is pretty damn clever.
In the 3D Printing community, MeanWell is considered one of the best PSU's to use. Any 3D Printer I build I always use a MeanWell PSU. They aren't even that expensive for the quality you get so no reason not to use it.
Very clever that thermal fuse, moreover adding the flux to wick faster the solder to the electrodes, someone was thinking. Nice to see a brand that match its reputation with quality, and they aren't terrible expensive.
Meanwell is quite the company .. I am always happy when I open something to look at the psu and its Meanwell. I was happily surprised when I got my new aquarium lights and it shipped with a 138W Meanwell power brick.
I have been using more and more meanwell components in my line of work as a commercial electrician and I have never been disappointed with the quality. They always seem well built and designed, their documentation is also clear and straightforward.
I've been using Meanwell PSUs for around 10 years, as part of a commercial product we ship worldwide. We haven't had a single failure so far. Great products, and a rare thing these days...
One of my professors was an old EE. We were looking at power supplies and we came across the MW parts. I said 'I just don't know about the brand'. Now he could have schooled me, but he just said: 'read their name, they say they mean well' 😊
When I first saw their name for the first time, the following phrase passed through my mind: "We MEAN well but we don't always DO well"
HAH - but they do, they do do well
I'm an EE, and one time an electrician questioned me about the quality of a Mean Well DIN-mount supply. "Well, at least they *mean well*." I think Mean Well is good but I started buying TDK-Lambda after that rather than convince these guys who have worked in the industry 5 times longer than me.
This looks too well made to be modern. It looks like something built between the late 70s and early 90s. Very impressive.
It's a Meanwell. This is a Chinese brand I do look for if I need a PSU that I know is safe and well made, usually with over provisioned spec.
@@dennis8196Taiwanese, big difference 😅
@@llary yes and the proper name for China is west Taiwan. Really silly error to make. Mia culpa.
That's a rather unfortunate thing to think about, something being not as substantial because it's modern. Backwards I stead of forwards.
@@llary Hehe
Meanwell = Doeswell.
Some really robust PSUs, at sensible prices (neither over cheap or over priced)
Taiwan designs and builds some really nice tools and parts, not much more expensive than Chinese stuff but very high quality
That's because the front office is in Taiwan. Most of the factories are across the water.
As the grid becomes ever more noisy due to solid state inverters, variable frequency drives, and switchmode supplies this sort of unit will become even more important. Good on you Clive for giving praise where praise is due, in these cheap as chips throw away times it's nice to see something built to be fit for purpose.
Ray.
Excellent teardown.
Meanwell is top shelf. Unfortunately they're discontinuing some of my favorite dc-dc LED drivers.
I used meanwell power supplies in automation for stuff where the standard din rail supplies wouldn't work.
My impression is that they know what they're doing and I've never had a failure.
Lately, it seems many companies are basing their business models on a "profit-over-quality, replacement sale of shoddy products" methodology.
It's reassuring to see there are still some manufacturers who prefer to build their business by releasing high-quality, robust products, and having their repeat sales be from pleased consumers. Manufacturers who operate in this manner definitely need to have a spotlight shown on them, and a TH-cam channel not far from a million subscribers (congrats!) is a great forum to do so.
"That is so tight! ... Yeah, that is very tight!" 🤣
Steady on, Big Clive! ... This is family electronics channel!
Nice to see a well constructed and solid product.
It makes a change from the cheap Chinese's - Poundland junk. (that we all love to see the awful mess inside🤣 )
In preferably, I mean mandatory, pink. @@dcallan812
It saved me a lot of bother and clutter to just get a whole-house surge protector for my junction box. Voltage spikes can get surprisingly high and I have a soft spot in my heart for MOSFET's.
That only protect you from surges coming into your home from outside. Point of use units protect sensitive items like consumer electronics from "bully" appliances like A/C units, clothes washers, and the like. Defense in depth.
@@railgap That may be a good point. Worth some thought (and reading some scope traces). Thank you.
A firm I worked for used to rebrand MW power supplies because they were so good. We sold thousands & never had a faulty unit returned - even when our own crappy products had done their best to release the magic smoke from the power supplies as well as themselves! 😂
So does RS.
Were they for Durable Communications?
I have come to trust MeanWell as a quality manufacturer and indeed you will find their products in industrial equipment designed to work hard 24/7.
I have one of their 150W power supplies, and all the mishaps I've had including short-circuits, it cuts off before the RCD at the fuseboard could take action. Meanwell are a league in all of their own and rightly-deserved, full credit for full engineering.
How any RCD should have done anything when the secondary side of an isolated power supply is shorted? Most secondary sides of switching power supplies aren't even grounded, so how a ground fault protection should help in this case?
The RCD would not react to a low voltage DC side short. It will be the units inbuilt protection that kicks in.
Back in the late 90-early 2000s I was servicing Personal Computers in a small store I had. The damage caused by lightning strikes was interesting and so preventable with such a device as this. It was amazing how hit and miss the damage to the insides of the systems would be, and back in those days, the modem (phone line) was what many times people forgot to put spike protection on. I would imagine that cable companies would have to protect their products when they bring a conductor into the house as well. Spikes can come from lots of directions, not just the power.
Where I live, cable companies often use contractors for customer premise installations, so quality is all over the map. I had a pretty decent installation and back in the days of analog basic cable I started to get nasty hum bars in my picture. I called the cable company who sent out a technician who drew a pretty healthy spark when he unscrewed the F connector. He muttered something about my ground was probably servicing the whole street. He put in a new drop and made new RG-6 jumpers, but I still had hum bars. I wound up buying my own ground isolator and that somewhat reduced the issue. Eventually the problem went away when the FCC started to crack down on cable system egress, so the company had to do a general system tune-up and get grounds where they were supposed to be.
Yeah, voltage spikes can really take weird and unpredictable paths sometimes. A few years ago, a lightning strike nearby managed to grill the network chip of my PC. The PC itself was protected by a power bar with integrated surge protection, but the router wasn't, and apparently the spike traveled through the router and into the LAN cable...
Can confirm, my mother would toast her modem at least once a year by leaving it plugged in during thunderstorms. Amazingly, ONLY the modems suffered damage every time. (PC still works, we retired it when support for Win XP ended, and it was too low-end of a machine to bother upgrading Windows. People laugh at eMachines, but the ONLY issue we ever had with that PC was Fried Modems, and that was clearly owner negligence.)
Our house was built in '75, with underground utilities, almost 300' from the pole, and we actually had a small transformer in the basement that fed AC to the phone line, so maybe this combination of factors saved us some grief? Well, I'd rather drop $50 or $60 into replacing the modem than the whole tower. 🤷♂
I used to be a part time cable guy, working evenings after my primary day job. I'd be driving to the cable job and see an electrical storm crossing over the town. I knew I'd have a stack of brand new tickets waiting for me. "Storm came through, cable box stopped working." I'd just take a whole case of boxes with me that evening.
The store I worked as a technician in had a system unit brought to us by an insurance adjuster after lightning strike damage through the phone line. Rather than unplugging everything the user had switched off the power strip.
Lightning had welded the slot cover of the modem and of an adjacent empty slot to the case.
He wanted to know if any of the modem, system main board, ram, cpu, power supply, hard drive or video card were 'salvageable'. With the cover off there was no visible damage beyond that the MOV on the modem board was discolored. We took everything apart and tested each separately. Nothing had survived.
i love the crew's "one moment please"
I have been unsing meanwell for private and professional use for well over a decade and never had one fail even at over voltages or other extreme conditions
I love how you finally take apart something that is rugged and of excellent quality, instead of the usual infamous China Export stuff.
Mean Well was always my favorite brand for known quality and not crazy high prices. (It also helped that their main stocking distribution warehouse was only one day shipping away 😉)
Well, with a cheapy chineese one you get a lot more bang per buck.
@@agurdel Yes, those cheapy Chineese ones do go "bang!" when they blow.
@@agurdel Yeah, but THIS unit was MADE IN CHINA!
@@uzlonewolf Yeah, but THIS unit was MADE IN CHINA!
I use Meanwell PSU for years and love them, amazing construction no surprise. Nice video 👍👍👍
Meanwell makes great PSUs. I have one of their 5v supplies that was intended for LEDs (iirc) that I use to power several security cameras and it's been rock solid even being outside for almost two years now.
We used to use meanwell power supplies for cctv rack power on off shore vessels. Always ultra reliable. Great gear.
I don’t or should I say didn’t know much about SPD’s but was contemplating their installation in our off grid setup, I definitely think this is our go to company now thanks Clive we all enjoy your work🇦🇺👌
Dang, that is proper industrial! Love it. The flux in the fuse is genius.
Meanwell literally saved out butts! Had to run one of their power supplies @110% rated for 24 hrs a day x 9 days in 50 degree heat. Had some equipment fail on us in the desert and had no other options... little guy took it like a champ and didn't let us down.
Will only buy MW :)
Mean Well PSUs are derated by 25% to ensure they can run at the specced current 24-7 without problems or affecting it's longevity so an extra 10% wasn't actually over it's real limit.
I had a project where I cheaped out and used generic chinese power supply and after the third one failed I got a Meanwell that never gave me any issues. If I’d gone for the Meanwell in the first place it would have been cheaper and a lot less hassle - lesson learned. Good kit and not much more expensive than the chinesium equivalents.
You learned your lesson. Buy cheap, buy twice.
Buy once, cry once
Sounds familiar. I have some alarm system gear in an attic that can easily hit 45C in summer. Chinesium PSUs worked fine all winter but failed in summer. After a few repetitions of that cycle I tried a Mean Well. It's survived 4 summers so far.
Do love Meanwell gear in general.
The conveyer systems at work, use 2 sizes of 24v units, and I've often joked with our fitters, I'll end up borrowing one for a bench supply.
Additionally I have used their 15amp based switchmode units, often found in various MAME video setup's, but in an Electrocoin Bar-X slot machine, Electrocoin themselves, often using the very same units in their video game setup's, noticed for their rock solid reliability.
Ironically actual classic arcade games from the 80's are infamous for their shoddy PSUs (and monitors, and poorly engineered mainboards) but then it was never thought anyone would be using them for more than a couple years at most so they cut as many corners as possible.
... We've seriously gone to a time where we're praising professionals for doing their dang job.
Let that sink in.
I have meanwell psus integrated in my workshop renovation. Mounted under desks and such for lighting and misc electronics.
I'm only just starting to play around seriously with electronics and that solder/flux fuse mechanism is just so very clever, I think.
It is very clever.
a similar solder type fuse exists in the automotive world, where two springy, wires are joined by a small blob of solder, if the wires get hot enough the solder melts and the joint springs apart. Found in heater resistors, so if someone doesnt change the cabin filter, and the resistor overheats(its just a coil of nichrome) it densest set the car on fire, just melts the solder. if your tight as a tight thing, you can simply re-solder the join to repair it !
apparently, epoxy potting compound can be relatively easily removed by boiling it for awhile to heat it up, and then it gets soft and can be picked away. I saw it on different youtube videos and I can't wait to try it on the next thing I have to depot. I used a heat gun which worked to soften it up and pick it away but boiling seems to be much more effective with less chance of damage to the device
I find it hilarious how your colleagues go a little crazy with your "one moment please" catchphrase
transient suppressors are the best investment ever
solid design and great built quality, not cheap
I've heard tons of praise about Meanwell PSUs over the years, and if those are only half as well built as this chonker, I can already understand why. They're also reasonably priced (not chinesium cheap, but not expensive either) and just work. One of my Raspi projects runs off a 5V PSU from them, and if any other DIY projects require power, it's most likely going to be yet another Meanwell unit ;)
"That is soooo tight. It is so potted. No time for a *deep* investigation."
We innuendo so you won't.
I've never seen this particular device but it doesn't surprise me it's very well designed and built. I've been using Meanwell PSU's and drivers for over a decade and I've never had problems with any of their products. I wish more Chinese brands would go this route of impeccable products at very reasonable and competitive prices rather than the usual route that cheaper is better even at the expense of functionality and safety..
Taiwanese.....not the West Taiwan....
@@JohnSmith-yv6eq I'm in Sub Saharan Africa. The MeanWell products we get are mostly from the PRC.
@@JohnSmith-yv6eqIt is both. The company is originally based in Taiwan but it also has a large operation in mainland China.
Very useful and instructive how thing can be done properly.
Lightning is a capricious thing. Years ago my house took a direct hit and random stuff literally blew up. It magnetized a TV screen but didn’t burn up that TV. The cheap phones failed, except a Western Electric CD 2500 was OK. I opened up one of the dead phones and there were wires sticking up and black soot on the PCB where a MOV had apparently been; it fought the good fight.
Obviously your monthly sacrifices to Zeus were not of sufficient quality, but not so bad he decided to destroy you. A warning shot.
@@LackofFaithify Yep, that Zeus is pretty fickle. I almost forgot, it happed early in the morning and when I got to work and was telling the story, a capacitor in a Televideo 950 terminal exploded behind me like it was a special effect right on cue. Got a lot of laughs.
A Televideo 950 serial terminal? That's a blast from the past.
@@user-gx6jb6wc5g Yep, from the age of Vax computers back in the 1980s.
FYI, MCOV = Maximum Continuous Operating Voltage
Hi Clive. Always wondered what those "One moment please" taken to bits, looked like.
Now i don't have to imagine some adventures. : } Thanks!
I had an ATX power supply in a lab instrument fail and was amused it was manufactured by a company called Meanwell . I showed the client and said they mean well but don't quite make the grade.
To be honest , the PSU had been running continuously for 12 years and failed after a power down / power up cycle - possibly the first such cycle in years.
The PSU enclosure was a very nice extruded aluminium design with integral cooling fins.
I Frist bought some MeanWell power supplies years ago from Jameco for a quick test of some fan motors. Given the price and the company name I honestly didn't expect them to be any good. I was mistaken. Today I have an assortment of MeanWell devices that have served me reliably. It says a lot that I am surprised to find a Chinese brand that I trust.
I'm sure someone has already said, but I guessed that MCOV stands for Maximum Continuous Operating Voltage and Google backs me up :D Very good video on an industrial component that many people will never know even exists and is doing important work.
Meanwell aren't well known to the general public largely, but we used them in industrial stuff all the time (control panels power supplies etc)- VERY reliable...
Big fan of Meanwell PSU's. Always use them in my projects at home.
The only dead Meanwell's I've seen are in a machine at work where they are wired in series and used to supply a LASER source. They work hard, and work 18hrs a day, so I can accept a failure every now and then.
When the outputs of two switchmode power supplies are wired in series it causes damage if one is turned off or cuts out, as it may reverse charge the output capacitors of the one that is off via the circuit.
Meanwell is a reliable standby for small power supplies. The construction here doesn't surprise me one bit.
I have used Meanwell powersupplies in equipment they really do build some nice stuff !
That's a well made unit.
MCOV likely means Maximum Continuous Operating Voltage. 300V AC in this case.
A lot of that circuitry is commonly found in many devices, albeit at much lower power ratings.
Instead of a thermal fuse, a fusable resistor is added along with a small fuse. First thing to check after a system goes down!
This is a great design though! What I'd have done in addition, commonly found in military stuff, is add a red led across the fuses, which lights up when the fuse pops.
Beats the lick your fingers and run them quickly down over all the banks of fuses while you're being fired at... The one where you get a zap is the culprit!
surprisingly, the removal of the circuitboard improves the separation xD
I now want to take apart one of the Ditek ones we use at work for protection on HVAC controllers to see if they are as good
In my design, I placed the silicon diode in parallel with the led but in reverse, to avoid exceeding the reverse breakdown voltage of the led.
I'm glad it was good, I really think this company Meanwell.
Thank you. Keep working, good luck.
MCOV = Maximum Continuous Operating Voltage
What's hilarious is he said "MCOV, not quite sure what that means, 300V that's the maximum continuous rated voltage without actually starting to shunt". So he knows exactly what it is, and almost said the exact expansion of the initialism.
Clive, I am very pleased to see you reviewing a decent product for once instead of the one pound trash that seems to invade our Facebook posts nearly every day. Well done!
If I'm fitting a mains power supply in my kit Meanwell is the goto supplier. Used them for years in both my hobby and professional designs. They always pass the required certification with no issues. Just fitted a 24V 100W one into my CO2 laser from CPC (Farnell) for about the same price as an unknown brand from Aliexpres. They provided the mains isolation that allows be to cut the daisy and not be pushing them up.😂
Definitely better than the usual Chineseum junk
MCOV - Maximum Continuous Voltage? Or Maximum Continuous Over Voltage?
following your reading of the text on the module, "mcov300vac" could be read as "maximum continous voltage 300 volts ac".
I've seen you try to get into other things with resin so I figured I'd offer this tip that helped me- I reccomend a small Ultrasonic cleaner/bath there are some pretty good ones on amazon for around $100-150 USD, preferably one that outputs of around 800+Hz & you can use either paint thinner or mineral spirits along with the ultrasonics to dissolve the resin/epoxy usually without damaging most of the components inside. (those LED's probably would be plastic free afterwards though) Another thing you can try is using rather warm Castor Oil, as most Endo/Exo-Thermic epoxies & resisns are made with it & as such it,
MeanWell is a decent brand, We use their SMPS modules (12 v @ 40 amps or higher) to power Digital 2-way radio communications transmitter power amplifiers
Another unit we use is their 24v SMPS modules mounted on 19" rack panels with 4 and 8 port PoE taps to power wireless bridge radios so we dont have little PoE injectors hanging about all over a site.
MCOV means just what you said (no surprise there). Maximum Continuos Operating Voltage.
they really mean it well
Great products from this company, have used many. Avoid buying from large distributors such as RS, their price can be 3 x the wholesale price.
Looks like CliveCAD has had a major realease bump, looks likely DaveCAD might have a lot of hard work to do to keep up.
An additional layer of protection would be to put gas discharge tubes in parallel with the MOV's, I designed something similar in the 90's; Furse & Phoenix contact make similarly robust products.
If you put the gas discharge tubes further up the line at the distribution board the induction of the power cables will keep voltage down and save MOV's from overheating at high energy discharges. There are ready made units for this.
Ahhh Furse, a name I remember well from Nottingham. They did quite a few things, lifts being one thing, and I know of one in pretty much unmolested condition at the old co-op (Now 3 Counties Snooker) in Long Eaton, Derbyshire.
Inside my UPS made by UPC, they use MOVs jacketed in shrink tubing, and a dedicated spark gap part, and call it good.
I don't know about other brands, but suspect they all do the same thing for as cheap as possible.
Wouldn't protect from a direct lightning strike. But it is interesting to try to wrap your head around the induced current scenarios these things protect against. The discharge lamps then MOVs to shunt the currents around the device, capping the voltage on the live input then the use of the bonded neutral/ground so there is a parallel path to cap the voltage spike on that side of the circuit.
You may find heating the resin in a saucepan will soften it enough to make it rubbery and peel away from the components.
Meanwells may be Chinese, but is proof that they can build good stuff. I use their power supplies, with no problems.
It’s nice when it’s tight.
It's amazing how affordable these are. Less than $20US. They make another model also, that cost less . The specs are pretty much the same accept it has a 10ka rating instead of 20ka.
I have been impressed with the Mean Well power supplies. I didn’t know they offered these protective devices until I saw this video. Thanks for the info. I think I may have some applications for these devices.
Not often you see a quality built for purpose electronic and electrical product anymore.
I have a 24v 1000w Mean Well power supply I use for my lipo chargers. In electric R/C "previously owned" surplus Mean Well supplies are commonly used for this because they cost about the same as a new noname PSU from china but are much higher quality. If a Mean Well supply says "1000w" then it can run at 1000w 24-7 with no problems, they're actually derated by 25%.
Was surprised to learn thatTVS diodes have the fastest surge clamping response, contrary to what i would have imagined, those little gas discharge surge arrestors which used to be used in telecoms are super slow
A surge suppressor is basically a big fat VDR or ZNR in your case.
I think 300MCOV has to do with the COntinuous rated nominal rms rated Voltage 300*root2= 424volts peak, which is in close agreement with the part number breakdown you mention earlier.
We used Altronix PSU for our security cameras. They always seemed well made and only failed when you went way over what they were specked for, like x3 the number of rated watts. Even then they replaced it but recommend moving up to a beefer PSU. It would be interesting to see a tear down of their products
Funny thing about the meanwell brand is that 15 years ago I thought they were the worst of the cheap. Now they are so popular that they are being ripped off by other makes. I can’t seem to get away from the later “MVV” brand.
Well meant and well executed :)
That's a really smart thermal fuse (without, of course, being a "smart" thermal fuse).
It is nice to see MOVs used in a way that plans for them to eventually fail. As for protecting a whole house, well this unit isn't rated for it, and so cannot be installed in a breaker panel (over here at least). There are similar units available for the purpose. Note that when doing so (in the USA), the unit must be connected through a dedicated circuit breaker, and both breaker and unit should be positioned as close to where the wires entire the breaker panel (from the meter) as possible. [there are also units which install in the meter base, but pulling a meter is a HUGE deal, so you don't see many of them. Maybe my smart meter comes with - it's the best place to put them!] - note also the unit should be positioned as close as possible to its breaker so that the wires between them are as short as possible. If you want to go premium, there are units which don't use MOVs, but bring money.
OBTW: when Meanwell put a CE stamp et al on their case, they actually have got the approvals.
We should all know by now that's not always (usually) the case for things coming from Our Honorable Communist Business Partners From China!
I wonder how much better this is compared to a tvs diode.
This seems better designed and looks to be slightly lower cost than most SPDs for use in consumer units 🤔
What a pleasingly robust and simple does-what-it-says-on-the-tin device.
MCOV Maximum Continuous Operating Voltage?