MCB Not tripping

[fire]

i have come across two showers in different houses where they have installed 32A mcb on a 9.5Kw shower. switched the shower on full and measured how many amps is drawing which was well over 32A but the mcb doesnt trip. any ideas as to why?

 

[Engineer54]

would you say its acceptable to have a 9.7kw shower on a 32a mcb? Surely this could be a no no espicially if the cable is 6mm or 10mm run under insulation.

In this day and age i suppose you have to follow Manufacturers instructions. But in the real world it is highly unlikely that your going to see that 9.7 KW ever being used, not unless your cooking a lobster!! lol!! No-one i would imagine would be able to stand the full temperature rating of these electric showers. So there is a very good chance that the 32A breaker and the 6mm cable would suffice to handle what's actually going to be used. Plus the fact that these showers are often only in use for 10 to 20 minutes at a time.

Trouble with younger sparks, they always over estimate heating loads, so cable sizes go sky high as well as the protection ratings. Some should really take an amp clamp to some of these appliances and see for themselves the ''real'' current draw!! I bet they will be surprised 9 times out of 10 just how far out they were... lol!!!

 

[Marvo]

I'm guessing that at 9.7 KW it would be one of those pumped showers with spray heads all over the place a bit like a mobile Hazmat wash bay.

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[Knobhead]

High pressure scalding hot water, that’s not a shower it’s an instrument of torture!

My shower is only 8KW, I don’t have that turned much above ½ way.
Just wish I still had access to a recording clamp meter to satisfy my own curiosity.

 

[Rockingit]

Just wish I still had access to a recording clamp meter to satisfy my own curiosity.

Would a 'max hold' one not suffice just for that job? When also used in conjunction with a pair of legs set on 'max dash' mode, of course.