The SI prefix M is Mega.

In combining the prefix with the unit name, the prefixes' final vowel is retained, except in the case of “hectare”. The American National Standard* also calls for the spellings “megohm” and “kilohm”, but the spelling “megaohm” is often encountered.
 
Megaohm or Mega Ohm or MΩ

It should never be truncated in spite of what the US does.

Things end up with different meanings, for example
1 millimetre is 1mm or 0.039"
1 mil is 0.001" or 0.0254mm

So giving a dimension as 156mil - is that really what you mean? Something around 5/32"

Annoys the hell out of me as insulation (dielectric breakdown) is measured in both V/mm and V/mil and people will say air is 3kV per mil - no it isn't you muppet air is circ 3kV per mm or 100V per mill (it isn't a straight conversion!)
 
It’s an insulation resistance meter, combined with a continuity meter, and nowadays performs earth loop impedance and rcd operational tests.

Some might call it a multi function tester….

Others still call it a “meggar”


As for the measurements taken… it’s Megaohm

Like megawatt, megaton, etc
 
What meter were you using? All I've encountered don't have an auto facility for IR testing and also have a delay when test button is held for this very reason.
Yes, for a while testers have been obliged to do this.
For some fun, you should try an old Robin KTS1620 (same as Kewtech KT62)
It's gloriously (and usefully) lethal!
Touch test and instant 250/500v/1000v to the probes, and the Test button can be locked on.....
I keep one in the van entirely for fault finding low IR, it's light, it fits in very small places and it tells you the answer in 1/10 second!
 
Once the initial jolt has passed you should be able to hold on to it, one of my party tricks doesn't hurt at all.
 
What meter were you using? All I've encountered don't have an auto facility for IR testing and also have a delay when test button is held for this very reason.
It's the kewtech 65dl. You push and quarter turn the test button. I'd hung the leads over the left hand side of the strap and they zapped the back of my hand. I can 100% guarantee it zaps on auto 😂
 
I think kewtech is a British brand. It does disable the auto if you switch between tests types on the 2nd dial, and forces you to reset back to manual before re-engaging auto. It's a nice little MFT tbh, I like it. Only niggle is the nulling of leads can be a pain to unlock and null again. 64dl is easier to null but not very clear if it has nulled
The null on screen feels ambiguous as to whether it's ready to set null or is nulled
 
I'm not sure exactly how they're connected but Kyoritsu is a Japanese manufacturer of very good test equipment and their testers are rebadged as Kewtech in some parts of the world. One of my other favourite tester brands is Brymen and they are rebadged as Hellerman Tyton as well sometimes.
 
One has probably licensed one from the other. All my fibre splicers are Japanese, either sumitomo or fujikura. Can't say I've had a bad experience with anything that says 'Made in Japan' on the side
 
Maybe in the UK it's a requirement for them to be idiot-proof but not in many parts of the world. I see they sell the digital version of my tester in the UK which also has a locking test button and no delay before test starts
Most MFTs state compliance with IEC 61010-2-034 which I believe stipulates a 5 second delay to all IR tests. (this appears to be one of the regular complaints about the new Megger X1)
I don’t know if this is voluntary compliance or mandatory, I’d assumed it was required but in order to sell it here.
That tester you link to doesn’t mention that standard so looks like I was wrong.
 
Most MFTs state compliance with IEC 61010-2-034 which I believe stipulates a 5 second delay to all IR tests. (this appears to be one of the regular complaints about the new Megger X1)
That seems a really annoying long time for most test!

Maybe if it only applied above 500V it would make some sense to give folks a moment to think "Do I really want 1kV+ on this circuit?"
 
Nice piece of kit the kewtech

I think I'm right in recalling that the analogue dial shows up certain faults better when troubleshooting

The fact that it will visibly flicker or move when testing variable type faults
 
That seems a really annoying long time for most test!

Maybe if it only applied above 500V it would make some sense to give folks a moment to think "Do I really want 1kV+ on this circuit?"
Seems a bit stupid incorporating a 5s delay

Would think a warning indicator on the higher voltages and maybe a "press to proceed" sequence or something would be better
 
Definitely an advantage of analogue meters, regardless or what measurements you are making.
Yes and recorded readings need to be exact for reference , comparison etc.

But generally speaking an analogue dial will tell you all you need to know when troubleshooting or testing
 
Yes for fault finding and troubleshooting which is the majority of my work analogue is always my first choice. The only time I would use one of those newfandangled MFT's (if I owned one) would be for EICR testing where you need a raft of test results recorded and entered onto paperwork.
 
That seems a really annoying long time for most test!

Maybe if it only applied above 500V it would make some sense to give folks a moment to think "Do I really want 1kV+ on this circuit?"
That's what the megger 1741+ does. No delay up to 500v but it will delay, beep and flash on the display for 1000v before it starts the test!

I favour an analogue meter for fault finding and still have an old Metrotest that I use for exactly this!
 
That's what the megger 1741+ does. No delay up to 500v but it will delay, beep and flash on the display for 1000v before it starts the test!

I favour an analogue meter for fault finding and still have an old Metrotest that I use for exactly this!
It will only do it on the first test at 1kV though. Repeated tests aren't subject to the warning.
 
As a point of interest, you can see the Megger X1 delay in action in this video, though in some cases it is edited out!
4 mins 46 secs shows a 250v IR test. It's painful!


On my 1553 you start to see the digital representation of the needle move immediately, and as I said above the old Robin gives an instant result. Progress, eh!
 
As a point of interest, you can see the Megger X1 delay in action in this video, though in some cases it is edited out!
4 mins 46 secs shows a 250v IR test. It's painful!


On my 1553 you start to see the digital representation of the needle move immediately, and as I said above the old Robin gives an instant result. Progress, eh!
Not sure how many times I've pointed out in the comments that he shouldn't be disconnecting the cpcs when insulation testing, and yet he still does it!
 

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What is it called IR testing?
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