IR Maths not adding up....

[Rockingit]

Currently on site and getting very confusing IR results on an EICR...any suggestions welcome!

TT @ 43.7
Ring with R1R2 values OK at around .5 as an average.
IR value consistently .049 R1R2.

Have SCOURED the place with the owner and no hidden sockets, spurs etc or neons.

Voltage is 233, so by reckoning that equates to a leak of about 0.047A. RCD ramps at 19.5 fine.

Can't see a testing fault and for sure there could well be serious rat damage, but surely with that Maths the RCD would never hold??! Confused!!!

 

[Silly Sausage]

Maths not adding up....


233/49k = 0.004755,
4.8mA




Is that what you mean, you must've missed a zero out somewhere?

I'm slightly confused as well

 

[Rockingit]

Thank you, yes that would be it! Damn decimalisation, knew it had to be a simple answer but wound up today. Cheers bud.

 

[Geordie Spark]

Thank you, yes that would be it! Damn decimalisation, knew it had to be a simple answer but wound up today. Cheers bud.

Never had these problems back in the days of pounds shillings and pence, yards feet and inches and pounds and ounces did we?? Unless of course you confused you pounds (currency) with your pounds (weight).

 

[Silly Sausage]

I only found out recently why we had learn times tables up to 12.
Because there used to be 12 pennies in a shilling!

I blame the above arithmetical error on too much cider...

 

[Geordie Spark]

I only found out recently why we had learn times tables up to 12.
Because there used to be 12 pennies in a shilling!

I blame the above arithmetical error on too much cider...

Only recently???

And there was me thinking you're a clivvor clogs !!! :laugh3:

 

[Silly Sausage]

Hahaha...that'll be because you've never met me! :smilielol5:

 

[telectrix]

and a dozen eggs at 3d each were 3 shillings. ssssimples.

 

[Geordie Spark]

and a dozen eggs at 3d each were 3 shillings. ssssimples.

Eggsactly !!!

Dunno why we had to change everything.

When engineering changed to the metric system, a lot of firms bought new metric sized drawing paper and re-drew all their existing drawings on the new paper and dimensioned them in metric and that was pretty much all they did to comply with the demand "THOU SHALL GO METRIC!!" All the machines retained their Imperial graduation dials & scales, and all the measuring equipment remained imperial too, so we had the ludicrous situation of the bloke on the shop floor sitting with a pocket calculator and pencil changing all the metric dimensions on the drawing back to the imperial dimensions that they were in the first place !!

When I became a Training Instructor, we trained the apprentices in the metric system and after their first year in the training school when they were fully familiar with sillimetres, they were let loose on the shop floor amongst all the machines which were ........ IMPERIAL !!

 

[Rockingit]

And the rest of the inspection revealed..... 3 lx ccts with no cpc, 1 faulty RCD, a cooker connected via a 1.5m 3 core flex via a 13A socket via more flex via the original cooker outlet buried 1ft behind the battened false wall (it was truly a beauty), no sign of an earth rod anywhere (verified it had to be there somewhere by measurement), a former immersion outlet made safe by chopping the flex off in the (childs) cupboard it used to be in but leaving live at the outlet, sockets with faulty earths, a 6mm shower cable and a 50A CPD..... etc etc etc. Rat droppings everywhere, all over the place. Have already patched one cable back up a few weeks ago. Rewire needed, but it'll be a sod of a job to do in what should be a very nice old cottage.

 

[Kieran Randall]

Need help with maths if anyone's willing to help....... Only an apprentice

Need to find the : impedance, current and power factor of a basic circuit

the supply is 230v at 50Hz

10 omh rresistor and a 40mH inductor

anyone help?

 

[Toonlad]

Just like the old woman in the grocers asking for 5LB of potatoes, and she was corrected by the grocer saying it is kilos now. So she asked for 5lb of kilos.. ..........