If I could run 240V from my panel, I would. I cannot. I am not the only person who cannot. Not everyone can make whatever changes they want to their electrical wiring. Do not buy one of these. They should not be used for kitchen appliances, they can't be used to charge your EV, and never leave one plugged in all the time. I only say all that because I have seen things online now that I've been researching them. One correction on what I said, apparently some places in the EU can actually get 4000W from the wall at 240V, so it is technically possible to use this at it's rated capacity. But that would be assuming stepping down which means you would need to pull that power back out through the plugs on the front at 120V, none of which are suitable for 4000W of power at the current levels high enough to hit it. So it either can't pull it from the wall in the US, or it can't get it can't put it out through the sockets on the unit. So I'll stand by my statement that it is massively over rated, not even taking into account the quality issues. There are other things about the build quality that I'm still finding are bad or didn't mention here. The fuse it came with is 30A and the breaker on the front is 40A, both WAY to high to be useful. The breaker is actually real, I cracked it open to verify it but I'm going to replace it with a 10A model and pair it with a 15A fuse. It gets worse though, the wires are all aluminum. Which means heat generated by poor solder joints will cause differing rates of thermal expansion in the wires making them basically self destruct.The transformer wire could be aluminum now as well which has other much worse implications. I don't know what a good option would be. At this point, I would instead want something like a UPS that just generates the voltage from scratch fully isolated and with better quality control.

@AliceC993

3 жыл бұрын

I can't think of a 100-120V device that's even capable of drawing that kind of amperage... as I understand it, most US appliances have a hard max design wattage of 1875, like hair dryers and space heaters.

@evefavretto

3 жыл бұрын

That thing is so shoddy inside I don't think it would pass regulations anywhere.

@trevormang7464

3 жыл бұрын

I believe Techmoan did an episode on voltage/frequency conversion when he tried to get a 60Hz turntable to work on a 50Hz circuit, and I think his solution will work for you as well. Basically what he did is connecting a 12v DC power supply to a sine wave inverter. With this config, you can change the output voltage and frequency of the output supply and it is isolated from mains. kzread.info/dash/bejne/kZibsZKBlLOzlNY.html

@graealex

3 жыл бұрын

Yes, we get about 4kW on single phase with 245V@16A, which has become the normal voltage. The only household appliance we don't have on single-phase is the kitchen stove usually, and even that only requires two phases (either 400V@16A = 6.4kW or 2x245V@16A = 8kW) plus another one for the oven. I understand that it is common in the US to have your washing machine and tumble dryer on two-phase 220V supply. And continuous power per device is still 2.4kW, as you're not supposed to draw more than 10A from a single outlet.

@shadowtheimpure

3 жыл бұрын

Perhaps the capacity is assuming the device to run multiple appliances simultaneously? Such has running a 1500 watt microwave plus a 1500 watt waffle iron at the same time?

That soldering looks worse than the kind self-taught 12yo me used to do with a big clunky Weller pistol-style soldering gun

@jorgeszabo1659

3 жыл бұрын

Sadly it probably was soldered by a sleep deprived 12 year old

A half hour video about getting a transformer to work, used to power up another transformer, just to get 6.2V AC in then end lol :XD 120V=>240V=>6.2V

@BilisNegra

3 жыл бұрын

Not just that, he needed to get it into working order to power a calculator!

Thanks for the explanation of the auto transformer. I knew these were non isolating (figured that researching isolation transformers) but wasn't sure what auto-transformer meant. Now I know!! My only suggestion is putting a reasonable glass fuse in there -- 4000VA is completely possible in some places in the Europe, especially in the UK which uses crazy ring circuits that offer 30 amps @ 240v -- available at a normal plug! I'd put in a 10 amp fuse to give you leeway with the 15 amp circuit you're plugging it into.

@TechTangents

3 жыл бұрын

I found out from this I vastly underestimated the power they have over there. That's a lot of power on tap for a house! Definitely on the fuse. I'm thinking of putting in a slightly less than 15A fuse and a replacing the breaker with a 10A model to have two levels of protection. I want to make sure this thing is massively under used whenever I use it in the future.

@mauriceleach3558

3 жыл бұрын

13amp is the standard uk plug, so 230 x 13a = 2.99Kw. but most of the uk is 240 x 13 = 3.12Kw. some plugs in industry that allow more

@Stoney3K

3 жыл бұрын

The UK ring mains don't allow 30 amps to be drawn on a single circuit. Most mainland Europe circuits are simple star-type topology from a single breaker, and limited to 16 amps off single phase. Our three-phase panels are 400 volts at 3x16A which offer a whopping 20 kilowatts, which makes cooking on an induction hob an absolute breeze.

@nebular-nerd

2 жыл бұрын

We need that level of power in the UK to feed our tea habit 🤓☕

*The DZ47-63 range of circuit breakers are known to be FAKE, inside they are just a switch and have no overload protection* You had me worried for a bit at the beginning there thinking you would plug that horror show in without reworking every solder joint in it, absolutely horrific workmanship! I doubt even the ¥1/hr worker who assembled that thing is proud of it. Things I still don’t like about it: - I would be worried about the quality of the transformer. However, as it’s an autotransformer it can tolerate a few failures of wind-wind insulation shorts however I wouldn’t be surprised if that pile has copper plated aluminium windings. - With the winding resistances you measured it will be dumping 300 W to 400 W of purely resistive losses at 4 kVA (depending on which way around you have it), magnetic eddy and hysteresis losses would drive that up more a well, fat chance that thing can dissipate that much heat safely. - Same goes for the other wires and components they might be aluminium or plated steel. - Check if the protective earth has good continuity between the plug, sockets, transformer body and *painted chassis*. - The fuse is probably some cheap garbage as well, you might want to replace it with a proper ceramic one with a conservative rating (slow blow). - There is no thermal cut-off on the transformer, something I wouldn’t be happy with on a transformer this size. - Check if the sockets have the correct size cut-out in the chassis and it’s not just glue holding them in that will come through with a strong pull. I bet they got their 4,000 VA rating from getting 250 V (typical device rating) and 16 A (max Europlug current), however clearly inside there are components rated for 10A. Also, there’s a minor audio glitch at 14:03 for me, not sure if it salvageable or even worth the effort to fix? And, your explanation of how an autotransformer works with aid from the Blender animation is by far the most intuitive I’ve seen, certainly worth the effort!

@TechTangents

3 жыл бұрын

It was such a horror show inside. I just scraped the wire strands on the earth wire I replaced, and it's grey inside. So they're aluminum, awesome. So, really, it needs to be completely rewired from scratch. I plan on replacing the fuse that is in it, which I forgot to mention in the video is rated for an astronomical 7500W, with a 1000W fuse because I don't trust this thing at all and nothing I want to run on it will be more than that. That should solve most of the concerns about the poor quality by putting a much lower cap and load on it. 500W would be a lot for me to draw from it. For 14:03, yeah I hear it too. It's minor enough I think I'll leave it though. And thanks! Intuitive is what I was going for! Sometimes just a little bit of animation can really help with the understanding something so I really felt the effort was worth it.

@WizardTim

3 жыл бұрын

​@@TechTangents At 1 kVA it should be dissipating about 30 - 50 W which I think this transformer could manage with forced air cooling however with the tiny ventilation holes I’m doubtful, you might want verify this thing yourself by putting a 1 kVA (or probably less) load on it and measuring the temperature, no clue what temperature rating the insulation is but an 85 °C thermal fuse mounted to the outer core would play it safe for 105 °C insulation. One problem with transformers with aluminium windings is while aluminium has ½ the electrical conductivity and thus dissipates double the power it is also has ½ the thermal conductivity, so the core temperature is much higher leading to a max load typically less than ¼ that of a similar copper one. I see Amazon 3rd party sellers (but fulfilled by Amazon) sell those things here in Australia, it’s tempting to buy one just to video it burning, I’m sure I could get a refund but I’m not sure what would happen if I returned it to Amazon as a burned husk, I’m doubtful they would do anything. I also wonder if the consumer safety commission here could recall them as they’re clearly illegally bulk imported.

@crazy_human2653

3 жыл бұрын

@@WizardTim It would definitely be interesting to see how amazon deals with the return especially if it is caused by the product being badly engineered and assembled. (which if you get one to self ignite I would hope the government would do something about it)

The shuko outlet on the bottom left is there because of grounding purposes. The universal UK-like socket does not provide grounding for the shuko plug.

Pretty sure Optimus Prime was also an Auto Transformer.

Shouldn't *ALL* of these connections be crimped? I thought it was a No No to use soldered connections in these types of mains devices? At any rate that thing is a piece of junk.

@willpreston6881

3 жыл бұрын

(Not licensed, take me with a grain of salt, licensed electricians please correct me if I'm wrong.) NEC 110.14(B) states that you can use soldered connections as long as they were mechanically secure *without* solder before they were soldered (i.e. rattail method, Western Union method, etc). To that end, you might as well just use appropriately crimped connectors and correctly-rated wire nuts for mains connections. The reason journeymen say not to use solder is because solder "locks" the copper wire in place, which may be mechanically disastrous if the wire joint needs to flex, but also, restricts expansion/contraction due to temperature changes, which can also weaken the wire. IMO: Solder is fine if there's absolutely no mechanical flexing, absolutely minimal temperature changes, and you expect to be putting a relatively constant, moderate load at most; or in cases where contact resistance is something you have to avoid. Otherwise, crimp wherever possible for mains connections.

@UnreasonableSteve

3 жыл бұрын

@@willpreston6881 Quoting the NEC doesn't really make sense here - it's intended for building wiring, not end devices. Soldering is definitely acceptable within devices. Interfacing to PCBs is almost universally with solder, and the vast majority are not mechanically secured without solder.

@willpreston6881

3 жыл бұрын

@@UnreasonableSteve Of course. My intent in quoting NEC is to try and source where the "soldering mains connections is bad" adage came from. I've soldered plenty of live-at-mains connections in my own circuits and never had an issue, and as you said, it's especially common when attaching to PCBs.

@AngDavies

3 жыл бұрын

@@UnreasonableSteve soldering that earth connection in particular is definitely dodgy though, under fault conditions the current will be high and the solder may melt and break the earthing, that's the main place reason for the "mechanical security" iirc

@michaeldeloatch7461

3 жыл бұрын

Not so, could make an excellent door stop.

Speaking of fixing high voltage devices, how's that mini computer coming along.

@AkirIkasu

3 жыл бұрын

I’ll be happy if he makes the follow up to the sd2scsi video he promised.

This quickly turned into a Big Clive video. You’ve got guts to try fixing this mess.

When I see this kind of shoddy work I'd rather go and rebuild the entire thing by just keeping the transformer, but change plugs, sockets and even the switch with something of known quality.

@evensgrey

3 жыл бұрын

Change the transformer too, really. I wouldn't want to be using any components selected by the same people who thought those connections were suitable.

None of those sockets are uk compliant. And the old uk plug has non shrouded live and neutral so a little less safe than modern uk kit.

@peterking2794

3 жыл бұрын

It's an MK Safetyplug, and it does have shrouded pins. I've used plenty of them in my time.

You get 230 V max 16 A from an outlet in EU especially in Germany ... so theoretically 3680 Watt

@MermaidSystem

2 жыл бұрын

The specification allows up to 253V max vor single Phase and with full 16A you'll get 4048Watt. But that ist an absolute edgecase.

That transformer diagram section was excellent, awesome job with that

So, since you were running 60Hz instead of 50Hz, did it overclock the calculator?

@JohnUsp

2 жыл бұрын

No because that adapter transform AC in DC

the retrocomputing world (and vintage guitarists) could use a solid but expensive unit that combines 110-120-220-240 isolated stepup/stepdown AND 60Hz-50Hz conversion either using a solid state inverter with lots of filtering or a geared motor-generator.

Lots of transformer fun. One of the weirdest ones we built was a 3 phase ferroresonant transformer for use in africa, had a 3 phase input with a plc and contactors so it could bridge phases if they fell over and the ferroresonant transformer would deal with brownouts. We has the transformers wound specifically for the application and they were quite expensive (we never actually sold a unit) But it could theoretically provide power to a 3 phase load @ 10A pulling 60A from a 35% undervoltage single phase input (wouldn't work for 3 phase motors of course without the phase separation but these were destined for telecoms towers)

Jesus, this thing sounds like a deathtrap.

@Merlinkatamari

3 жыл бұрын

It is save to use when you know what you doing just RTFM and i have to say that this thing is build down to a price so don't look at it :D

What a bodge job, random guage wires, hidious soldering, heat shrink flapping in the breeze.. just terrible. Make sure to ground that metallic enclosure btw

@dieSpinnt

3 жыл бұрын

Did you see the sockets? Continuously cold soldering points, even on the protective earth. Attached with hot glue. That just calls for a break, which means probable death. Immediately in the trash with it! Or use a completely new housing with approved sockets and proper grounding ... which will cost as much as this junk. Extremely dangerous that part!

@dieSpinnt

3 жыл бұрын

@@Ormaaj People do shit.

The autotransformer woks similarly to Variac. Doesn't look too bad, it just needs to be completely rebuilt. I would also bypass the voltage switch, it looks pretty crappy, and replace all the sockets with European ones.

By the way, electric frequency is also very important. Most countries in the world use 50 Hz, but North America and South Korea use 60 Hz. As for Japan, Eastern Japan (Tokyo, Sendai, Sapporo) uses 50 Hz, while Western Japan (Okinawa, Nagasaki, Osaka) use 60 Hz. On an additional note, I was able to get a fat PS3 from Japan running from a 120V supply, as Japanese outlets have a maximum rating of 125V (100V is used officially).

@mgladders

3 жыл бұрын

Weird that Japan has both standards within itself. What's the story there? Anyone know?

This doorstop doubles as a fire hazard and vice versa - whichever of the two is the intended feature

Looks like the Chinese found a use for the recycled solder from salvaging e-waste.

I have a little brother of one of those that had exactly the same QA problems inside...really dangerous stuff. But after repairing it works ok and I used it to test (at VERY low power) a ham RF amplifier just to ensure it was operational. Caveat Emptor!

If you want a SAFE (well built) auto transformer, you should look at Nissyo (Japan) or Hanil (Korea), not Chinese built crap with cold solder joints.

Putting 60Hz into a power supply designed for 50Hz can on older ones cause damage. When I worked for Tektronix, we had many supplies fail early because they were designed for 60Hz and we used 50Hz and vica verca.

@JendaLinda

3 жыл бұрын

50Hz power supply running on 60Hz is not a problem as long it's not loaded at full power.

@salan3

3 жыл бұрын

@@JendaLinda disagree. I have had many transformers burn out due to this. They can overheat.

@salan3

3 жыл бұрын

@Lassi Kinnunen 81 Agreed. It's the older transformers that def do not like.

@eDoc2020

3 жыл бұрын

Running a transformer-based power supply (or motor) on a lower than designed frequency is more likely to cause overheating and damage. Running something on a slightly higher frequency is very unlikely to cause damage and in fact might lead to slightly more efficient operation due to reduced magnetization current. Of course this is just theoretical. Other variables or unusual power supply designs could have unexpected side effects. Always use care and monitor closely when using anything outside of its designed ratings.

@salan3

3 жыл бұрын

@@eDoc2020 I am going off my own experience when working for Tektronix. We had terrible trouble with power units designed for 50hz running on 60hz and vica verca. Also when the 2215 scope came out they had problems as the designers in the US did not have a low impedance 240v 50hz supply. This caused part of the protection cct to short. The first demo models in the UK had to be run with a pigmy bulb in line (hidden under the bench) to stop damage. Power bricks often had short lives if the had been run on the wrong frequency. Today this is not a problem but it used to be.

Fantastic video! Very fun. Thank you for making it.

12:55 omg that WAS the fuse, by soldering it you bridged it :D

That plug would not pass UK regulations.

@electricdragon9366

3 жыл бұрын

That plug looks like a shucko plug for some weird reason

@pederb82

3 жыл бұрын

UK plugs don’t pass European standards at all. But yeah that one would not even pass the UK one. Weird how you can be an electrician there with a tiny little week long course

@evensgrey

3 жыл бұрын

That's not a UK plug. It looks like a grounded Europlug, which is incompatible with UK plugs (which are the safest AC connectors ever made).

@imranahmad2733

3 жыл бұрын

The 3 pin plug moulded on the 3 way switched extension cord is not even fused like a UK plug, I wouldn't be surprised if the cable in the extension is just copper clad aluminium cable.

@Alexis_du_60

3 жыл бұрын

That's a CEE 7/7 "French/Schuko" combo plug meant to pluhg either in French CEE 7/5 ("Prise type E") outlets -and- or German "Schuko" CEE 7/3 outlets .

So, now we have fixed this 4000 watt behemoth weighing short of 40 pounds, we are finally able to power some calculators...

It is very common for these to be autotransformers. I have only seen one that was an actual isolation transformer and that one was in a lab. That said the construction of this one is really poor.

@russellhltn1396

3 жыл бұрын

A big advantage of a autotransformer is the power handing. In this case, the transformer only has to handle half the rated power (2000W), not 4000W like an isolation transformer. When stepping up 120V to 240V, the autotransformer has to handle all the current of the load, but only has to create half the voltage. That's because the input line voltage is "in series" with the transformer output.

14:40 time to rebuild the hole thing and just keep the core x3

Similar devices are routinely sold to US military personnel overseas (not that brand, and not so poorly constructed, I hope). I had one in Germany, sold it to an incoming soldier when I returned to the States. I still have a couple straight plug adapters that would let you connect the transformer's original plug into a USA outlet.

I know we're all used to seeing incorrect and impossible statements of fact on the specs for cheap import equipment, but the 4kW isn't too far off the rating of that mains plug on the stock device; 16A at 240V, so 3.84kW . Now, my guess is the wires would melt if you ran it at that but strictly speaking the plug at least should handle 4kW.

Big Clive would be proud!

@anotheruser9876

3 жыл бұрын

But ElectroBoom would have been very disappointed.

@nebular-nerd

2 жыл бұрын

I imagine @Voultar would have some choice comments about the soldering as well.

Great video, I learned a lot.

I skip (dumpster for Americans) dived a distributed audio system CD carousel unit years ago when our local Borders book store was being refurbished, because the units were American in origin I also had to grab a multi tap power strip along with it. The strip was wired into a fairly dodgy looking step down transformer with no enclosure or any other safety features. Still have it to this day and would trust it way more than that steaming heap. Excellent video, you've got a new sub from me.

I've used one of these before. Back in 2002 or so had a customer with a PC from Europe with a 240VAC only power supply. The customer provided one of these step-down transformers, but wanted the computer's power supply replaced with a 120/240VAC switchable unit that they typically get here. They didn't bother replacing the power cord on their step-down transformer, instead opting for a simple NEMA to Schuko adapter.

Those solder joints look like they were made with random AliExpress solder (which you can never be sure is the advertised type).

If you had a non-hazardous version of this sort of thing, is it worth replacing the captive cable with an IEC socket so you can then freely swap between us/europe/uk/etc. power cords?

An autotransformer! It remaind me the electrical machine lesson at school. At work we had 2 step down transformer (i live in italy), one diy with a big isolation transformer and a Roland one similar to this, we use for american artist that need 110 volts on stage (now in the show biz we have a lot of thing with switching power supply that support both 110 and 220 volt, but a lot of guitar amp for example work only with "home" voltage). An for @18:50, in my City we have a proton therapy center, and when they build it first they had make foundation, put the accelerator and then build the building around it!

A Variac also is autotransformer. Also just 3 wires (unless there are some optional taps. The benefit of the autotransformer is that the core power rating is double relative to an isolation transformer.

The virgin 120V AC vs the chad 240V AC

@Moonwalker917

3 жыл бұрын

Beautiful and efficient 240v AC vs chubby high current 110v AC

I like how they labeled the Schuko plug that is not polarized

European AC single phase sockets *are* in fact 230V, 16 amps, which is a smidge under 4000 watts.

Our transformers in the USAF over in Germany and the UK to convert the 240VAC down to 120VAC for electronics we had in our houses from the US were also autotransformers. They are not isolation, and do not claim to be. You are right the wiring on the input has to be correct to get the desired output voltage. Before plugging anything in to the output, use a multimeter to test first.

You should throw that C40 Breaker (which is also fake without any fusing elements (Magnetic or Thermal) away and get a nice switch. Since you're using a small gauge wire, you're limited there anyway. Also the breaker in your home would trip way earlier.

@und4287

3 жыл бұрын

Seconding this. Toss that garbage and get a proper one (though that form factor of breaker is uncommon in the U.S.)

Alright that's cool and all but why not just run a 240v circuit? I suppose portability is handy but if you're just gonna plonk it on the bench then I'm confused.

@evensgrey

3 жыл бұрын

@LabRat Knatz Actually, he said he can't have it done in the pinned comment. That probably means he's in rental housing, where you can't get anything the least bit non-standard installed, like an extra 240V outlet.

What is that weird plug on the power strip? Is that the dodgy Chinese shrunken edition of our UK plug?

Can't draw 4kW on a single phase? Someone needs to send you an English Kettle! :D

I used one of these for several years. Mine was 1500VA, and had an IEC input plug on the back, for easier input changing. I used it to power a 220v only PC power supply off US Mains.

@YesterGearPCii

3 жыл бұрын

I also never used a power strip on mine, as I only needed to power the one device.

what kind of extension is that TT?, the plug on the end looks like a 3pin with round pins, that is what the uk used before the oblong pin 3pin plugs we have now, its very obsolete. if you need a proper uk plug 240v surge protected extension that can be arranged.

22:13 where did you find that plug? It's not a UK one. 😬

The circular lower left socket is called "SCHUKO" and is used in Europe.

What's that odd plug you're holding at 22:00?

oh. I found one of these in the trash a few years ago. I haven't plugged it in. One of these days, I'll either use it as is, or harvest the transformer for a spot welder or something.

That crappy solder job is the same as was inside my Chinesium powered soldering and hot air rework station. I felt ridiculous using and old school soldering iron to rework the solder connection inside my new soldering/ hot air rework station, but at least now I trust the integrity. Copper plated aluminum is actually very common because it is cheaper, AND aluminum has less resistance, making it a more effective conductor. Being clad in copper keeps the ocidation issues to a minimum, but it is WAY harder to properly solder as the wire wicks away the heat so fast that it is difficult to get hot enough to get a proper non-cold solder connection without burning the next half inch of wire insulation to a molten puddle of goo. Add to this problem that most manufacturers have to use the lead-free solder to comply with RoHS requirements and you end up with some pug-fugly joints. Here in the US you can buy the leaded solder (with lower melting temps and more crack resistance), but individuals don't have to show RoHS compliance in their repairs. Now, if that sounds bad, the crimping down on the insulation is really bad. Soldering small wires going into a lug isnt as bad as large wires, but a much better choice is either bare wire, or my preferred mothod of crimping on a ferrule, which is just a short peice of metal tubing that gets controllably crushed holding the individual strands together in a mechanical way. This way all of the conductors are under the lug (no single strands popping out the side) and are all carrying the current right at the junction, which is where most faults occur (weak joint with few conductors carrying the load cause localized heating, which raises the resistance which in turn generates more heat). That's a viscous feedback loop if ever there was one (rivals telling your wife that something was wrong with what she made you for dinner)..... Nice video. Really like the explanation of the auto transformer. Very similar to the multi-tap transformers used in many industrial machines. Just remember that is is not an isolating transformer. I hope to god that you didn't do all of that to be able to plug in the calculator. Hope that was just a test. New sub here.

The "4" on the back panel looks out of place with the other text...

@wesley00042

3 жыл бұрын

Yeah, looks like someone turned a '1' into a '4'.

@alejandroknopf

3 жыл бұрын

There are probably different models with different ratings. They just change the leading number to match.

Some doorbell transformers have directions for using them as an autotransformer. Granted they only step it up or down by like 24 volts.

Is there a reason to not use a switching power supply for this sort of thing? Surely you could have a switching power supply output AC? It should be far lighter at least.

This might have been said already but... I'm pretty sure the plug on that power strip isn't UK compliant. If I remember right, it needs to have a fuse in the plug and the two power pins need some sort of sheathing at the base so you can't accidentally touch them while (un)plugging it.

@zarach11

3 жыл бұрын

A month late replying but that's definitely not a UK strip, I think it's India? Maybe he bought it because the sockets are fairly generic, it's a Belkin who are a reputable brand but that old white plug which he plugged into it is an example of UK standards not the round unfused black plug on the extension lead

Might as well just run a 240 volt circuit from your breaker box, assuming you have that capability

@LeoInterVir

3 жыл бұрын

Or: 1 find two 120v circuits that are not powered by the same mains line 2 get an outlet box 3 get a 240v outlet 4 connect hot from cord to one 240v outlet connector 5 connect hot from other cord to other 240v outlet connector 6 mount outlet in box 7 plug in cords to 120v outlets, that are not sharing the same mains line 8 congratulations you now have the 240v that's actually supplied instead of the 120v used Notes: 3 wires connect to breaker box 2 hot of 120v each 1 neutral breaker box connectors usually alternate 120v circuits between both hots for load balancing 240v circuit connects between both hots in breaker box

Hell, "I" could have built a better device than what came from the manufacturer in this case. I consider myself a rank amateur, but the errors on this are egregious.

@BertGrink

3 жыл бұрын

Fellow amateur here; i fully agree with you. The moment i saw how the wires were soldered i thought to myself "holy shit man that looks like total garbage".

First time I see one of your videos. I wonder about the schematic at 10:35 since it is only possible if you cut off the plug and wire one in wrongly on purpose. The guy making the article clearly blew his stuff up somehow else. If you rewire this unit (wich certanly was needed) how come that you kept the option to step 240 to 110 ? Much less hassle and possibility of faults to just wire it for 110 to 240 and make a new front labeling. Do you ever need this one to go from 240 to 110 ? Good on you to clearly state that this one is not an isolation unit. Very important ! Thanks. When you showed your benchmeter, please clean it and wash your hands several times a day please.

Sockets designed to fit many different types of plugs fit all of them badly, with a small contact area and tend to overheat. They’re not good even with small loads, but I’t certainly not use anything carrying 4 kW, like this

For the algorithm- let’s get you to 100k.

One other issue with this sort of transformer is that it's still 60Hz, not 50. Some things will work fine, some things won't work at all, and some things may appear to work but are overstressing internal components. Also, a lot of bathroom scales aren't really accurate for anything lower than 50lb or so. (In a pinch for a check you can weigh yourself with and without the item and compare.)

I just have a 1000W Toridal medical grade isolation transformer unit I mounted in a box to turn 120V to 240V.

According to Technology Connections channel, you already have 220v in your home.... cant remeber the video name, but he shows how you get it from your fuse box

@mullahviking

3 жыл бұрын

@Lassi Kinnunen 81 which ironically the same system we have in Norway except we don't use the neutral.

@NaokisRC

3 жыл бұрын

That dedicates that line/room to it. This is for singular devices really. It is possible but TC was saying that's how to wire in a EV car charger.. which makes sense. You want the high voltage and current, but for a computer, you don't need that much hassle.

You didn't need the power strip as the British 13 amp plug would have fitted the same socket.

Is there a roll of solder anywhere that doesn't have a sliver of the top of the spool missing?

@paulmccoy2908

3 жыл бұрын

Or just hanging on by the sticker.

That round pin plug is not European, I believe it's Indian, although if it's the small 6A type, we also use them (rarely) in South Africa. And yes, just buy an inverter, a Victron Phoenix 12/250 230V for example.

In Ontario it's actually illegal for a thrift store, any store really, to sell or even give away something like this since it lacks safety marks like UL

You should really get an isolation transformer. Not that it would completely mitigate the hazards of this device but it's good to have on the bench anyway.

also triple lead transfromers are common, if you have ever looked at cheap welders , you know, and the fire hazard is actually a cooling problem not an electrical problem, if you only give it loads that its designed for it should be ok, but a case fan can make these type transformers last for life.

Given the number of multi country fit none plugs on the front I'm sure your supposed to use it with those death adapters on the input as well rather than changing the cord....

Makes me wonder what the factory conditions are

Reason it's rated at 4,000w is because it's rated on 240v power at 16A. 16A circuits are very common on European 240v systems. When using as a step up transformer, take the current rating of the circuit you're powering from and half it. That would be your output. So a 120v 20A circuit will give you 240v 10A out. So 2,400w. And the loop is called a Ring circuit. Again, very common in Europe.

Rule of thumb when buying cheap electronics from overseas... If it has a plug that goes to your wall, open it and verify that everything is soldered and assembled well before ever plugging it in. I've seen these issues pop up with nearly anything 120 or 240 volt... Soldering Irons, Hot Air Stations, Air Filters, you name it... If it can be put together, it can be put together badly!

I had a 5000VA ups that took 4 group-34 batteries. Its transformer was around 100 lbs. It was surreal.

I realize the build and component quality was junk, but this is actually a clever circuit. You often don't need isolation, just voltage conversion. And if you do rewire and rebuild it as you did, it isn't that bad.

Here in the UK we get 3KW on our residential sockets at 250vac. Never seen 4KW on single phase household in the UK, but the EU is different to us.

Is that weird triangle plug from Europe as well? I could recognize the UK one and the one you removed from the transformer. But the triangle plug you put in I have never seen before.

@ZeroViruzz

3 жыл бұрын

It looks like the Indian power plug, which is based on an outdated UK one

@imranahmad2733

3 жыл бұрын

It's one of them unsafe, unfused moulded plugs that come with most Chinese electrical gear, I wouldn't be surprised if the cable is copper clad aluminium.

@DaimlerSleeveValve

3 жыл бұрын

They used to be normal in the UK, and thus spread to the empire. That one was rated at 5A, but I wouldn't be surprised if they pulled 15A iin some places. They are still available in the UK, but the good ones have shrouded pins for live & neutral.

The rating of autotransformers like this one are double the rating of what you would expect for the size of the unit. You can look this up in EE textbooks.

It has the three different plugs because one is needed for grounded European plugs (set in circle), one works with UK but not grounded European. They probably were cheap and used the other two due to price

bigclive would thoroughly enjoy that thing

For devices rated 220-240, US 240V will work. For devices rated 220-230 or 220 only, the voltage will likely be too high (I get about 248v from the wall) always check the input voltage ratings!

@mvevitsis

3 жыл бұрын

@LabRat Knatz yes, I'm running many vintage devices rated 220-230 only, I do not plug them into US 240V service. For this, a 230v transformer is ideal.

@mvevitsis

3 жыл бұрын

@LabRat Knatz I recommend either Nissyo (made in Japan) or Hanil (made in Korea). Nissyo has been making transformers for almost 50 years, and Hanil for nearly 40.

I always forget that your plugs only go in one way, unlike the ones I'm used to in the Netherlands.

Don't you have a variac there? It's the same principle, except there's a variable "tap" on the autotransfomer that you can control with a knob. It doesn't provide isolation either.

@Stoney3K

3 жыл бұрын

Correct, this one is an autotransformer with a fixed tap, while a variac has taps on each turn that connect to a wiper.

Maybe I'm missing the obvious here, but why not use the 240v from the breaker panel? Dryers, ovens and garages usually have 240 outlets. In a pinch I've found two outlets feed from opposites sides of the breaker box. (The latter is highly NOT recommended)

@DakalaShade

3 жыл бұрын

Not everyone has 240v coming from the panel. I'm in a house with a gas water heater, gas dryer, and gas stove. All of the breakers (save for the main incoming) are single-phase, so the best you'll get at any outlet is single-phase 115-125V. Finding two outlets fed from either leg of the breaker box would work, but can lead to some rather amusing, or interesting, problems in the event of something failing. If something shorts and pops one breaker, and you reset said breaker, you might not necessarily trip your main breaker... You might blow one of the two main service fuses instead.

@ericnelson4540

3 жыл бұрын

@@DakalaShade Well, I AM being a little presumptuous. I've added a few 240 outlets in the house for higher voltage applications but I also understand that this solution may not be for everyone. One other totally bonkers idea I want to try is using one of my high power amplifiers fed with a 50 hz signal into a step up transformer to feed some PAL devices. Not that it's a good idea, more because I want to see if it will work. 😁

@David_Phantom

3 жыл бұрын

Some people don't live in a situation where there landlords like them install, or let the, have someone else install, stuff like that. As he said, if he could do it, he would, but he can't, so he shan't.

@deathventure

3 жыл бұрын

@@DakalaShade All US homes have 240volts incoming into the panel regardless of the appliances or breakers inside. The panel input is 2 120V hots, 1 Neutral, and 1 ground. A single phase 240V breaker just takes up 2 spots in the panel, and provides 2 hots which give the 240V needed for certain appliances (and heaters). In the case for domestic 240V, it's 2 hots, 1 ground, where the 120V is provided by the 1 hot, 1 neutral, 1 ground.

@DakalaShade

3 жыл бұрын

@@deathventure I know how the 240v US system works. In my house, if I wanted to add a 240v breaker, I would have to upgrade the breaker box because every slot is filled.

The hot glue is a giveaway on quality.

I would review something like the Australian code to ensure you have the correct wiring. That doesn't look right to me, especially the chassis earth and order of the fuse connecitons.

Should get rid of the (cheap) switch and simplify it for your step-up application. Also get rid of the bottom-right connector and get a real UK socket. Those universal things are not safe.

Holy cow that solderjob.....

My grandpa has a couple 220110v transformers, from back in the days when Spain switched to 220V, and they needed them for their old 110V devices. He still has a drill press that works at 110V, which he uses via one of those transformers. However, it's nothing like this. No switches, just a 2:1 transformer with exposed euro style plugs on each end. While that has its own kind of risks (you should NEVER use a two-ended plug, because of the exposed mains!), it also is an extremely simple device with very few points of failure, and I feel like seeing how poorly made this was, it may have been safer to use one of that style..

@SeanBZA

3 жыл бұрын

I had a few of those, complete with the double ended suicide plugs as well, and they work, to some degree, though what you get as output is roulette every time you use them, as the non polarised plug is easy to put in backwards both in the unit and the 2 pin adaptor into the wall supply.

Tan Tech Gents, what a great anagram!

Sure 230V you can get via one of them transformers, but how do people in those lesser countries go about getting 380V for bigger equipment, like your household welding station, compressor, drill or lathe?

And what kind of device would do the same and generate 50hz from 60jz???

@hicknopunk

3 жыл бұрын

I have a transformer adapter I bought in Japan in the 90s, it outputs 100v at 50 or 60 hz depending on what you want. I have never seen one in the USA in a department store like this one.

@jordanhazen7761

3 жыл бұрын

A DC power supply feeding an inverter is really the only way. Like a scaled-down version of the frequency converter stations used to send limited amounts of power between 50Hz & 60Hz parts of Japan. or placed at either end of an HVDC transmission line, or to move power between grids not synchronized with one another (e.g. Texas' ERCOT & Eastern Interconnection in US).

Or....you could have located a good old fashioned "filament transformer" (6.3VAC out) intended for US use and spliced it into the calculator's power wire in place of the 240VAC brick...

It looks like the wires inside are going to go up in flames way before you run 16.7A / 240V or 36.4A / 110V through it. That fuse had better be less than 10A or less. No way this thing is going to draw 4000W without trouble. Autotransformers are not by themselves dangerous, as long as you are aware that the input and output aren't separated. You basically just have to care as much about staying away from the outputs as you would have to with something that's connected directly to the mains. And a ground fault interruptor in your house will actually work if you connect something to this that has a short between live and ground, unlike a separated transformer.

@TechTangents

3 жыл бұрын

I have bad news, the fuse it came with is 30A. Knowing that it is an autotransformer and how it works is what I wanted to convey initially for this video. I just got distracted by the fact that mine and seemingly every one of these for sale was assembled by the lowest bidder's stand in who had barely heard the word solder before. Autotransformers should be fine, as long as everything is done correctly with them. About the only thing right with this one seems to have been the polarity, and that's about it.

@JacGoudsmit

3 жыл бұрын

@@TechTangents Yeah... If that fuse is 30A I have some news about what your actual fuse is going to be when you have a short... Recommended wire gauge for 30A is 12AWG. It looks like that thing has something like 18AWG. (www.powerstream.com/Wire_Size.htm)