Doctor Drivel wrote:

When having RCBOs tripping on L & N, there is s high safety factor.

There is no safety factor. With a current
path only from line to neutral an RCBO is
no difference from an RCD or fuse and will not
trip until the full current is exceeded. If this
current exceeds the capacity of the appliance
lead fires can result.

The ignorance of this one holds no bounds. He is saying that if there
is an earth fault the RCBO will only trip when the current rating is
exceeded. Which defeats the purpose of an RCBO.

Where did he say that? I think you have reading comprehension issues.
Peter made no reference to earth faults.

1. If there is an over-current fault on the circuit it will operate the
overcurrent detection part of the device, which will trip the RCBO.

2. If there is an earth fault on the circuit it will operate the earth
fault part of the device. This will also trip the RCBO.

The above two points are mutually exclusive.

Odd that you claim this is not the case with a separate MCB and RCD
then. I refer to your assertion that a blowing lamp will trip a RCD.

So which of your pronouncements is wrong then?

There are two separate sensing circuits contained within the one RCBO

No, three actually; Thermal (overload), Magnetic (fault), and Current
Imbalance.





--
Cheers,

John.

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