One of those drove me nuts recently. The batteries were low and it started making faint beeping noises at random. It too me ages to find it because there was such a long delay between the random beeps.

Industrial Electrician in Sydney. You're correct, Dave, the Neutral and Earth in your building will be linked at the main switchboard then the submains to your individual tenancy will have 3P+N+E conductors. AS3000 forbids multiple MEN links within a single structure.

Re Toshiba laptops from the mid 80s, I was a Uni lecturer in a non-STEM subject, but a keen computer hobbyist at the time. I persuaded my Head of Dept to buy me one. It cost a fortune. I was interrogated by the Purchasing Dept as to why I should have one, but in the end they relented. That plasma display may seem crappy now, but I can tell you that to switch it on in the presence of someone unfamiliar with them, with it's power up screen flashing bright orange before creating a skeleton rendering of the Space Shuttle, was to make them gasp in astonishment that such wonders existed in this world.

When i was little, London got changed from DC to that fancy AC stuff - so Dad thought he'd have the 'Professionals*' over to do a rewire - I was a pretty keen kid, and as they were wrapping up I used their tester - "hey you've got live and neutral the wrong way" - 'don't matter - , its AC!" I might have mentioned it once or twice but things got left, until...This coloured spotlight had a 'continental' 2 pin plug, meaning I had to stuff something in the earth pin of the shuttered 5 Amp UK socket - used a screwdriver, and BLAMMO!!! The silence of midnight pierced by an explosion in my hand I don't move for a mo, and after the blinding flash, smoke clears to see plastic fragments and molten metal where plug and socket used to be... The Euro plug had an Earth strip, which had pinched into the flex, so the screwdriver had shorted the 'Neutral' to earth without ONE SINGLE FUSE between me and the company box! So.. Its always good to check ;)

I'd very much like to see a teardown of the Fluke ST240+ to see how it compares.

Yes. It's bonded in the main of the building, just like a house. In the US we have isolation transformers everywhere dropping 480v to 208/240+120v so those transformers have to be bonded again because they are a new service in effect.

Dave, you know us, we ALWAYS want another teardown!

Throughout North America, ground must be bonded at the service entrance at the first means of disconnect. Ground must not be additionally bonded at any sub-panel as that would allow current return through that ground conductor segment.

The RCD tester is basically what tells you whether you have a swapped neutral and earth. Although any device plugged into the outlet would trip the RCD either way.

Unfortunately here in Norway we use the IT (Isolated Terra) system, so earth is at the midpoint between the two mains pins in the plug, type of wiring (well older instalations use it, newer uses the standard TN wiring), so this units will just show an error all the time.

I’ve got a Klein Tools tester for 120 vac outlets here in the US. It’s got a nice LCD display which is easy to read and the GFCI test tells how many mS it takes the GFCI to trip. I’m pretty sure the separate CORRECT and FAULT lights still work even if the batteries for the fancy functions go flat. It was only about 20 Yankee bucks, so barely more expensive than a sketchy no-name Chinese tester.

I'm using it since 2 years BC (before corona) really helps in trouble shooting instalation.

The DaveCAD made my day

@1:00 THATS WHERE MINE WENT! Lost mine about 10 years ago…it was a good little tester.

Looks like you could toss one of those paper (?) diffuser layers and make the LCD much brighter.

7:32 The Type C socket has been banned in Europe, but may still be found in Russia. Type C plug is still available in Europe. This fits E, F, K, J and L. Also fits smaller UK Type C. Unfortunately it was not possible to agree on a type E or F socket. But almost all devices have plugs type E+F. This also fits into Type K sockets without connecting PE, which is why Denmark wants to switch to Type E. South Korea also has type F. Italy has types L and F. Greece Type F and another. The Swiss type J does not fit Brazil's type N. It has failed to introduce Type J across Europe. I think type D + M fits in South Africa and India. Type H in Israel. The British Isles have Type G and a smaller Type C in the bathroom. But the C sockets in UK also accept the European type C. However, the smaller UK Type C plug does not fit in Europe. Types A and B belong to the US with 115V, but there is also Type A in China with 220V.

Hiya Dave, as a pommie electrician, I would never use a product like that at all. I wouldn't trust it. Personally I have the fluke you showed earlier in the video. For anything more complicated I would use my multifunctional testes (earth fault loop tester, IR tester, RCD tester, phase and volt tester). You will probably have a TNCS system and your earth will be tapped off the neutral from the transformer instead of the supply cable.

Interesting and complex, over-complicated even. I know about these 3 LED quick testers, that inspired me to build my own a few years ago and it comes in handy for quick tests when I do any wiring work. I like the NCV feature. Nicely reverse-engineered too. As for relying on anything with batteries in it, I always test the gear on known good cases before doing the proper test. Still, I'd design it with a supercap and mains-powered charging circuit.

putting the switch through the hole in order to be able to load and solder the pcb from just one side is smart. Except that one led i guess, that one they probably handsoldered along with the battery terminal and stuff.

In Brazil, neutral and ground are connected close to where the wattmeter is. Unfortunately GFCI isn't mandatory (at least in family buildings). I find cute the way Aussies and Brits rant about their outdated plugs with exposed pins are the best ones for domestic applications.

I would LOVE to see a demonstration and teardown of the Fluke ST 240 +.

I've had one of these for a few years, the LCD is bright on mine.

In the MEN system in Oz, the NE link is made on the main board, NEVER on sub boards.

I see they also make it with Type F plug... but in the side-contact usage these plugs are symmetrical and there is no established L/N connection standard. So it will display "incorrect" then you can just rotate it 180 degrees and it will display "correct". Not very useful...

I owned one of those and had to dispose of it as the bulbs which illuminated the display failed. I used it at work testing extension cords on construction sites. Good unit overall, could have been tougher.

If you buy one of these to use frequently, make sure it has a short length of cord with a plug, like the cabac version, so much better to use!

In the US, the neutral and ground should be bonded at the first means of disconnect, after the meter

Nice one 😁

I have one of those since about 2 years and it served well so far for testing my self made electrical installation in our garden shed. Also my LCD is not that dim as is yours. But to be on the safe side I have a „dumb“ one too with just 3 LEDs to cross test. Never trust just a cheap Chinese thing only when it comes to mains voltage.

I don't have one of this type, but there is a meaningful scenario that these battery powered ones can help with or at least theoretically, which is when you have one hot wire disconnected some distance back in the line and so your meter would read some induced voltage, probably low but could still easily be over 30v with no capacity to drive the circuits of these devices. Scenario was I was using a fluke plug powered one for a wiring job in a out building and it took me a while to realise the fuse on one of the lines was blown before the box and my recent run was a-okay. Would have realized right away with a voltage reading and these plugs make it more certain your reading is making a good connection than a set of probes. Editted just to say I have the exact fluke model you brought up. Would love to see you tear it down so I don't have to :)

Hey! I have a T3100 laptop... love that thing.

Live - earth reverse on those is likely a broken neural instead. If there is anything connected to the circuit and neutral broken, the device passes the voltage to the neutral. The tester sees only differences, not voltages to the actual earth. In Finland testers must have a metal pad you touch to detect voltage on the earth contact.

I have 2 of those for US sockets and used them a few times for changing outlets a few times already .... mine have bright displays. They don't work with nimh batteries so make sure you have good 1.5V alkalines in there.

245v during office hours, we have 226v at night!

Just a question, What's "dangerous" about live and neutral being reversed? I. Live in a country with shuko plugs (seen in thumbnail), and those are reversible. Socket testers aren't a thing here as well, if you wat to check correct connections you use a duspol or something similar.

been carrying a Deta Power Outlet Tester Plug on my keys at work for about 25 years so long the once clear body of it now has a yellow tint to it only use to to tell if the GPO has power easier to use that than to wander around with an angle grinder

Swapping the neutral and earth would result in tripping your earth leakage breaker as soon as you plug something in right?

Wonder what it does when you have high earth resistance (in my case old house corroded rod in earth)

3216 resistors were the first SMDs I encountered, back in the 1990s, and I remember thinking they were tiny. The ones in this device look positively huge! How things have changed .....

is it just me or is the socket upside down

Cool!

isnt the rcd test if you got one a test for earth neutral swap as well?

When I was doing housing I used Duspols exclusively. I know how to read it and I found it more convenient than a tester like this

Dave, love the video mate. I recently purchased one of these (Also live in Australia) and it's not tripping any RCD's in my home. Did you also encounter the same problem? Cheers buddy 👍🏽

At least this didn't drop during the NFL Halftime show.

A bit of a sod to use if the plug is upside down, I think. In most of Europe, apart from France, their plugs & sockets are reversible, so how does it cope with that? Cheers!

Are there a standard tolerance for NCV detectors.? or is it simply anybody's guess and 100% up to the maker when they will shout&trigger first, will obviously often intensify the closer you get. Picked up a relative cheap MF/RF/EF sensor tester and Im seeing first trigger/alarm at quite steady 100 V/m on quite a few of my meters, not least fx 210E clamp meter.

Dave, can you show us sometime anything fun that one might do with those programming pins on the chip that you highlight at 18:57? What are all the possibilities when one has access to those pins- like, can you do anything fun with a JTAGulator or BusPirate (or Glasgow Interface Explorer)? Would it likely be limited to simply reading the chip ID out?

I was a military electrician and went to Kuwait in the early 2000s. They used the old BS (red yellow blue for three phase) and didn't bond the neutral and ground. Installing or disconnecting circuits would draw an arc due to the imbalance. Only other place I've encountered similar was Afghanistan that used Russian standard (ungrounded Euro plugs) with random Chinese panels that you had to provide your own bus bars, and often, installers would use terminal blocks with daisy chained 1.5mm² that would catch fire when a single wire was carrying the entire neutral load of the panel lol.

If it's a 6K4 resistors for the RCD detector, does that mean that resistor is dissipating 9W until it trips the breaker? What would happen if the RCD wasn't working? Is there an inline fuse?

The M.E.N. is (in australia) ALWAYS at the location of the Main Switch, so not in a sub board, So Power pole, meter link, meter, main switch, physically where M.E.N. is, then off to sub boards and final circuits. Also, I'm fairly sure its Main Earth Neutral, not Multiple Earth Neutral. To be boring, those RCD testers aren't illegal, but you can't really achieve any legal test with them, they are a gimmick or good for finding with RCD covers a power point, or possibly used to test earth continuity the long and trying way. A Legal RCD test requires ability to record time, change mA setting, and test each half of the wave.

I couldn't use them in industrial electrical work, because I had everything from 24Vdc all the way to 33kV ac, so I stopped using Duspols and I've used a fluke ever since

I feel like its a real missed opportunity to not use a transflective display to help with indoor and outdoor viewing

Please make the video on how you found the PN.

Cool bro, a DMM chip inside a socket tester? I can buy Jaycar's meter kit fully assembled at a discount store for 1/8th of its kit price. Only drawback is the transistor test socket is missing. Cristal clear display.

I have one of these, it's useful. But was delivered to me with the plug wired backwards (line and neutral inverted)....

I use mine for over a year now and the display looks OK. I think you have got one with a dodgy display

I think if the RCD is defective and doesn’t trip then the 6.4k resistor will let the smoke out if you hold down the button!

My uni-t ut 203+ shows for example current flow of 6 amp from black wire of battery and 8 amp from red wire, batteries are 12v+12v series combination in home power backup inverter. Please a little hint of information here, why there is current difference and which one to follow for calculating the proper power usase.

Personally, I'd probably trust the 3 neon version more than the MCU one. Assuming, of course, that each of the 3 neons is good.

So if the RCD doesn't trip how long before you smoke the RCD test switch?

Since we are upside down, they make the chips upside down, so the electrons dont fall out

Can the ground to neutral voltage go negative? Would comparing the neutral to live voltage with the ground to live voltage be useful? Ground to live should be bigger if wired correctly?

I think rev N/E would trip an RCD, but not older fused premises.

And in Poland, even with a Polish plug, this device is 50% usable

en.wikipedia.org/wiki/AC_power_plugs_and_sockets list of most of the mains plug types. Note that the US has an unusually large number of variations based on current and voltage capacity of the power point. And Japan varies both voltage and frequency.

I find it a bit funny that if only green lights, it's not really safe, you need "alarm red" to make it read "safe"

Is that upside down for AU/NZ ?

Ya broke the good one!

I am so tired of inverse LCD screens. So many have crap viewing angles and unreadable in daylight. And they require constant backlighting. I assume they are stylish because they look sort of like a computer monitor, and they can more easily have colored elements. I'll take the classic neon-style any day. Reliable, dead-simple.

Looks like you probably have to get down on your hands and knees to read this in a low-mounted outlet.

I bought a similar one from Mastek MS5902R that also injects a test frequency back onto the mains. Then a non-contact gun type thing can be run down the circuit breakers, allowing you to determine which breaker is powering that socket outlet. . Similar to the Klein circuit breaker finders, but about 1/5 the price.... works good enough in non-commercial applications, and easier that plugging in a radio and flipping breakers until the music stops 😂 . Only easily available with EU and US plugs, so I modded mine with a IEC socket so I could add whaterever cable I desired.

The Men would be in the main switch board. If not at the transformer.

That old safety tester was around $9.95 30 years ago.

oooh non-compliant plugs!

atleast europe has cheap 3phase so we dont need 100amps on single phase. also you wouldnt rely on something that has 2 tripple AA batteries inside it? too bad then because almost every electrician primarely uses Continuity, Current and Voltage Testers that have batteries inside them.

I have a few of those simple ones. Used it when wiring up some outlets. I think you'd have to try and reverse earth and neutral. The bare earth wires connect to the metal box.

Non compliant AU plug? No insulated pins for N and L.

Sure you can detect earth neutral swap, just press the rcd test, if it doesn't blow the fuse then it's swapped... or rcd is bad

That display is atrocious!

Its actually not an "aussie" plug but actually a mainland china plug, which happens to be ours but rotated 180 and without insulation on the L and N

from + 12:16 yeah, goodbye boring as. Instead of actually testing it, perhaps analyzing it effect with some measurement tools and manipulate it, to display some of the things it does, not least its 30mA RCD (as you explained you would).. nothing, instead you constantly crave to hear your own voice while making drawings. I dont blame you, as a parent that is what we do with kids, so it likely makes you feel good and perhaps reflect your childhood...as in hearing you own voice while making different drawings. Big Clive is honest about it, it resamples his childhood, when making drawings and hearing own voice - it reminds him of his mother & time there...

The German and French sockets may legally be swapped live and neutral. The usual system has 230V between neutral and live (240V in England). The electricity system in Europe is always three-phase, i.e. the phases are offset by 120°. In addition, there is still the old system rarely. The voltage between Live and the other Live is 230V; between Live and PE only 127V (120°) The apartments are then wired like this: Apartment 1: L1 & L2, Apartment 2: L2 & L3, Apartment 3: L3 & L1. Everyone gets 230V between phases at the sockets. This is not to be confused with the US split phase system. There the phases are opposite. 115V + 115V = 230V Everyone gets 115V at the sockets.

There is something wrong with that display. I have the same device and the brighness is just fine.

Up side down for Chinese market. 7:34

where abouts in Australia are you as interested in your channel and live in Brisbane, im also on your forum, which is fantastic

If they had used a non stupid LCD, they wouldn't need a backlight at all and the battery life would probably be great

Hey - where did those batteries come from? Or has Australia adopted our Canadian biligualism policy? (19:16 -'NON DESTINE AU COMMERCE DE DETAIL')

Why is it upside down?

0:16 It's got a Chinese plug, none of that Yankee or Aussie rubbish 😂

That's not an Aussie plug. It's upside down. It's a Chinese plug.

In Canada the MEN connection isn't permitted. Has to be a people connection. 🙄

WHY you have that funny power plug?

not sure why you consider the european plug "rubbish" 😞

i bothered to watch the rest of this. great to see the good old 7500, no seriously i never seen this chip before 🤔

How many types of mains plugs? TOO MANY❗

All of the electrons are going to fall out cause the plug is on upside down

Older, type A RCDs can only detect AC faults. This is why the reverse diode is needed in addition to the LED, to provide the negative current. The type A RCD will not detect half wave rectified DC. Nowadays the regs require the use of type AC RCDs that will detect pulsating DC as well as AC.

I might as well use one of my 50 DVMs to measure mains plugs instead of spending money on a new one of these testers.

The plug is upside down 😂 thats the Chinese for ya. I believe the uk plug has the earth on top as well.