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I get what you mean but the problem with these cords are that they are not fixed to the device. So even if they would be ok for the device it came with, there is no guarantee that the cord won't be moved to others. I suspect my cord came with a Banggood hot air station (Atten clone) which peaks at more than 700W. That's nearly 3A which I think is already on the unsafe side of this cord. I think some manufacturers care only for money and have a total "don't care" attitude to safety. They pack the cheapest cord, and fit the cheapest fuses, both of which are very often fakes.

You could nowadays wire a mains led lamp/fixture in your house with very thin wires given the very low current they consume, the problem is if something shorts or overload on the end of the wiring, since it has "high resistance" it will melt and catch on fire because the current wasn't enough to trip the circuit breaker, and that's the big problem with these dangerous pieces of trash, and some of them also have really crappy plastic that easily falls apart

I agree that if you want to use it as a independent volt meter you need to power it separately. The input resistance is generally not too bad (in the 100K range usually but always check). Current to power the meter depends a lot on whether its display is LCD or LED based and how high the supply voltage is, so a general statement is difficult. The same green LED 3-digit meter for example used 9mA at 5V or 25mA at 12V and the 3rd (measurement) wire has an input resistance of 150K

It uses AC instead of DC so depending on the rest of the circuit, things may influence the result. For example a capacitor in parallel will not disturb a DC measurement but it will cause an error when a resistor is measured with AC. Then again, the much higher DC voltage used by the Fluke (up to 1.3V according to the 87 user manual) may cause a PN junction somewhere to conduct which ruins the DC resistance reading. So you can't generalize and say it can't measure in circuit resistance. Yes it can and so can the Fluke or any other meter but the results of any in-circuit measurement by any method need to be carefully considered before taken at face value.

@@TheHWcave Yes, that's why it's totally useless for me.

I don't have a Mac so I can't give any opinion on whether something works on a Mac or not. I am normally using Linux Mint but have an ancient Windows 7 laptop which I sometimes use for compatibility tests or trying out Windows programs. I would assume that if stuff works under Linux, chances are it may work on a Mac too. In this case, Buspirate is open source and a quick Google search seems to indicate that you can use it on a Mac but as I said, I am no expert of Mac OS flavours.

That would depend on your country so the best way is to use your local eBay and search for completed sales of AVO 8 to get an indication. In the UK prices are relatively high because of nostalgia and/or collectors, so good looks fetch more money than a beaten up one but where everything still works accurately. It may be in other places, people rather want to use it not exhibit it on a glass shelf. It all depends.

@@TheHWcave Perfect @thehwcave, thank you very much for your message, I'm going to find out. Greetings from Argentina!

Great story. I am sure this "high resistance" cord was put there intentionally and people knew it would get hot. These fake cords on the other hand are sneaky because these days people do not expect a "curtain burner"

@@TheHWcave absolutely, people were aware of the risk*. It was just the thought of a high resistance wire that brought to mind that old technology. :-) * I realise, as I typed that that some people must not have been aware, or the term wouldn’t have been coined!

Its here: ruclips.net/video/Jr42rQMymN8/видео.html

@@TheHWcavethank you very much.

I like the idea to put a glass fuse into the plug in case someone in the house borrows the cable to power something else.

DODGYYYY

There isn't a "best meter", only one that best meets your specific needs and budget. Consider what you want to measure at what accuracy and at what protection level for user and meter. Also consider reliability, repairability (schematics / service manuals) and if you can recalibrate it, given you have the equipment. There are lots of meters that are far cheaper and yet have much better specs than Flukes but lack in protection and service documentation. There are some brands, e.g. Brymen that have the same excellent level of protection as Flukes and still slightly better specs at a lower price, but no service docs. Fluke is commendable in putting user and service manuals on their website and Flukes hold their value if you decide to sell it. So it really comes down what your priorities are.

@TheHWCave I really appreciate you taken your time out to answer my question in such a detailed manner, you have given me much better idea on the pro's & con's of purchasing electrical testing equipment as a novice this information is invaluable to me as you covered everything and honestly could not be happier and could have asked for more, I'm privileged to have found such a useful channel such as this to learn from, and I will definitely be subscribing, Thankyou.

It is true that the capacitive load needs to be considered when using this and lower caps would be better.. Unfortunately one of the problems is finding suitable high-voltage rated capacitors (from reputable distributors). Any probe will in some way influence the device under test. I think your example device would be extremely difficult to measure without notably influencing it. You would probably have to design a specific (possibly active) probe for just such a case and even parasitic capacitance would need to be avoided. Consider that even if you left all capacitors out on my probe and the scope had no input cap either,, the pure resistive divider would load this converter already with 2W

There could be many reasons for this, from issues when loading the binary into the microcontroller to incompatible hardware. As a start, the binary is compatible with the hardware I got and this uses an ATmega328P and is similar to the MEGA328_COLOR_KIT but I had to do changes in the display pin assignment to make my board work. It is quite likely that your version uses a different display. If you know your type, check the comments in the config files (I marked all my changes) and select your display instead. Another way (that i used) is to run the kit with the original firmware that came with it (assuming that gives a working display) and measure with an oscilloscope what each of the display pins do, then tweak the config file to get a matching pin out. Not easy and it took me many versions to get it right.

@TheHWcave i used your modified version code. Can you tell me you hardware pin out. I will correct it on my board. And one more thing what Crystal you using in your hardware? 16mhz or 8mhz

@@pcmobiletechnicalsolutions8504 The only information I still have is what I documented in config_328h (marked with <<TheHWcave) . My board uses 8 MHz clock frequency

@@TheHWcave can you please tell me where in the code i need to change if use 16mhz Crystal?

@@pcmobiletechnicalsolutions8504 I am afraid that is set in the MakeFile. Look for the line FREQ = 8 (for 8 MHz). You would need to change that to 16 but then have to run the makefile, i.e. recompile the sources and create your own binary.

It is impossible to be sure because you would need to know the brand and model of the resistor and lookup the datasheet. A 1/4 watt resistor (e.g. TE -Connectivity CFR series) is rated for max 200V, other brands have different voltages but they are probably in the same ballpark. The TE datasheet doesn't say AC or DC, other brands like Vishay say "AC/DC". That is important because 125VAC is the RMS value and the peak is therefore 1.41 times that value or 176V which gets close to 200V and leaves little room for spikes. But the TE datasheet also states it has a dialelectric strength of 400V. If the existing resistor is as good or better as a TE CFR, you should be fine, BUT (that is a big but) we don't know if the brand used is anywhere as good in quality (not likely if you ask me...)

I would still contact Fluke. It is possible they still do a replace since its a safety issue

Hi my fluke T110 has 2015, on the label on the back does it amongst the recall batch please thankyou

@@sloopycat1954 Mine says 2018 so I assume yes. In any case, I would quote the serial number to Fluke.

Hi @TheHWCave mine does not seem to have a serial no anywhere, only a barcode & barcode no with the date 2015, on the recall form link that you kindly attached there's a box you can tick if you do not have a serial number which was very convenient and the form was easy and straightforward, after pressing submit a message appeared saying they will send a stamped addressed package for the recall, fingers crossed hopefully they will consent just have to wait and see now, thankyou so much for all your help I'm really grateful.

I agree but I went through the Bulgin catalogue and could not find one that had the right dimensions.

@@TheHWcave The plug used for the Bulgin socket on the back is type PX0649, of course it's now discontinued.

@@factorydavid Yes, I downloaded the datasheet and it looks like a match! Many thanks for identifying. I saw one on eBay but way too expensive, so I will stay with my home-brew solution.

Totally agree. I have now seen pictures of at least two other A203Bs and they all differ from mine and each other.

Yes where I work we still use them, the guard switch is for an interlock. You can't just use a microswitch as its not intrinsically safe, microswitches can easily weld or break.

usually there are two "guns" with a live needle and a trigger on each one (the two trig switches are connected in series, non latching for safety)

A foot switch is a possibility although I would consider this unsafe as it is fairly easy to accidentally activate it - and thereby the timer & high voltage - when you don't want it. Not sure why they did not put the switch into the front plate. Maybe because the front was covered by a perspex safety cover? Maybe the original trigger switch allowed for activation from a fair distance for safety? Or maybe the original trigger it was a key-switch, i.e. only an authorised person with the right key could trigger the timer?

@tizianob8590 the one I used was like this. There was also a key switch on the front panel, the key being kept well out of reach of the uninitiated...

I remember building a test rig using a Clare unit like this over 30 years ago. As you say you would plug in the DUT (e.g. 13A moulded plug), put down the safety cover (like a cover over a turntable/record player) and the test would start. Switch was industrial type hidden underneath. I don't know the test voltage used but we weren't too precise, typically using 3KV where 2.5KV was required, same for the trip level! Clare were THE name for this kind of tester in those days.

The buzzer certainly can make you jump. In the video I lowered the volume quite a bit. My model is however relatively tame compared to other models that have way more power. Still I treat it with respect.

That is an excellent idea. I will do that as well.