Mcb makes a popping noise on resetting

[stuartR1963]

Hi all, as usual whenever a lightbulb blows in our house it trips the breaker which is pretty normal,it did it just now, on resetting the mcb it makes a fairly loud popping sound, it resets just fine but it just startles me a bit, it has done this most of the time on resets, it does not buzz or crackle or anything serious like that it just makes a brief pop.
Is this fairly normal? Could the noise simply be because i reset the mcb under load (there were a fair amount of lights switched on), or could it be that something is failing inside the mcb?
The mcb is a hager type b6, its one of the older types with the black levers.
Thanks

 

[333rocky333]

Some do make a strange unexplainable noise when switched under load

 

[stuartR1963]

Some do make a strange unexplainable noise when switched under load

Thanks so as long as its not buzzing internally which it doesn't, there is no cause for concern?

 

[333rocky333]

Personally i think its fine, its a funny noise, like when you was a kid and put your finger in your mouth and sort of flick your cheek
Thinking about it I think you do hear it more with Hager breakers

 

[bernardgreen]

An MCB should not be operated ( neither to ON nor to OFF ) when under load.

They are designed to go OFF under over load ( that is their purpose in life ) but the contacts are likely to be eroded each time it happens. How many times can an MCB operate to OFF before contacts become significantly degraded. The mechanisms are ( should be ) designed to ensure a rapid separation of contacts to minimise the arcing,

Switching to ON is a different mechanism, contact closing time depends on how fast the lever is operated by the person, It could be a quick flick to ON or a tentatively slow movement in fear of a big bang.

How much degradation can an MCB take before it can no longer be relied on to do it's duty,

There is something to be said for fuse wire, it is single use and cannot be re-used after it has performed it's duty. Degradation is total,

 

[333rocky333]

Newer BS60898 MCBS can be used for FUNCTIONAL switching, so wouldnt that also be the case they can switch under load too.

Even though its not a normal operating practise.

These days in commercial and retail it could be a nightmare to remove all the load.
We used to change loads of C50 Crabtree breakers in shops as they installed and used to use them as switches when they first came out, by the late 90s a lot became floppy and worn out