6 Amp RCBO 13 Amp load

[Top Cat]

Doing a rewire at the moment in an empty house. I am using RCBO's mostly so when i got 1 room complete i wired the 4mm radial into the RCBO so we could get the kettle going.

After several brews i went to disconnect it only to find i had wired it into a 6 Amp RCBO!

The trip never operated once with a 3 KW kettle on it. It was a Square D RCBO.

Going to swap the breaker on Tuesday when the merchants open but surely this should not happen.

 

[Octopus]

Try plugging in a 13A heater and see how long it holds for!

 

[GLENNSPARK]

this is it....the fuse (13A in this case)...is protecting the cable for this kettle.....doesn`t mean its pulling 13A..lol...

 

[telectrix]

if it's a 3kW kettle, it should pull close on 13A, but you know what liars these manufacturers are.

 

[Jdsparky]

The thing is the kettle would have only been on for a minute and breakers tend not to trip until 1.5 times there rated value...which the kettle would have only just been over that, but then would take a certain amount of time before it trips anyway, which you would have to look at the graphs in the regs book to find out how long it would take...you will probably find it takes longer than boiling a kettle!

 

[D80]

MCB's and RCBO's don't trip that quickly at there operated current. Page 301 BGB has the time/current characteristics for type B MCB's/RCBO's.

 

[Paul.M]

A 6A mcb/rcbo will hold 1.67 times its rated capacity for up to an hour so if you only had a kettle on it would need to be over 10A to trip, that's if the kettle pulls 3kw.

 

[Paul.M]

e3 people all said the same thing at the same time.

 

[Engineer54]

The trip never operated once with a 3 KW kettle on it. It was a Square D RCBO.

Check the time/current characteristics for a 6A MCB and you will see why. 3KW Kettles are normally only drawing current for a couple of minutes, for a full kettle. Half full of water, then even less time...

 

[Top Cat]

Cheers guys.

 

[RISElectrical]

Next time you put the kettle on, clamp your ammeter on the cable at the MCB... All will become clear

 

[telectrix]

Next time you put the kettle on, clamp your ammeter on the cable at the MCB... All will become clear

funnily enough, just done that. clamp in main tail, current reading 2.4A. switrched on 3kW kettle, reading up to 10.8A. so 3kW my arse!

 

[Engineer54]

funnily enough, just done that. clamp in main tail, current reading 2.4A. switrched on 3kW kettle, reading up to 10.8A. so 3kW my arse!

That's around a 1KW less than stated at 240V, complain to the manufacturer!! lol!!

 

[D80]

Glad I'm not the only one to have put the kettle on lol.

My 2.2Kw kettle pulls 2.3Kw (Got a keypad meter here which will give your KW load, load cost etc etc), got a voltage of 244v at the moment though so its about bang on.

It's a damn site more accurate than clamp metres.

 

[GLENNSPARK]

That's around a 1KW less than stated at 240V, complain to the manufacturer!! lol!!

saying what?...`you cheated me out of a KW`...lol.....