Immersion heater problem

[Adam_151]

Putting aside the fact that this post is older than ...erm... an old thing

Anyway:

In this case I even wonder if there is not a fault on the element causing it to take excessive current.

That's not really possible.

I'd argue that it is possible if there is no RCD protection, if the insulation of the element fails.

I'd not be happy with ommission of overload protection to such a circuit (to give a link back to a long running thread of a while ago )

 

[EFLImpudence]

I'd argue that it is possible if there is no RCD protection, if the insulation of the element fails.

Would your argument stand up?

I'd not be happy with ommission of overload protection to such a circuit (to give a link back to a long running thread of a while ago )

Your happiness depends on the above.

 

[Adam_151]

Would your argument stand up?

Unless someone is going to point out my logic is unsound, then the only way to disprove would be for someone to test it, unfortunatly I think there are a lot of variables involved.

I would hazard a guess that in "myth-busters speak" it would be "plausible"

 

[EFLImpudence]

Well, that's not really fair if you don't explain how it could happen.

 

[JohnW2]

I'd argue that it is possible if there is no RCD protection, if the insulation of the element fails.

Would your argument stand up?

We've been through this before on a number of occasions. In the absence of RCD protection, it's theoretically possible with any element which has an earthed casing (which develops an element-to-earth fault somewhere along its length), but whether it ever (or significantly often) actually happens in practice, I haven't got a clue.

In terms of the requirement (or not) for overload protection (which is the usual context of the discussions), I think we can probably agree that it is 'not likely' to happen (even if it happens once in a blue moon), so omission of overload protection per 433.3.1(ii) would, if one so wishes, seem to be in order.

Kind Regards, John