transformer tripping mcb

[pc1966]

Type D are rare as few loads need them, and for higher current type D MCBs it can be hard to meet the 0.4s disconnection time for final circuits (you need quite a low Zs to hit the magnetic trip to meet that specification).

They tend to be for protecting sub-mains (when 5s on the thermal part is OK), but are not as good as fuses there in terms of selectivity with downs stream MCB/RCBO. Or for high inrush things like big transformers and motors, again not a common domestic type of load.

Also if you are regularly switching a load that needs a type D MCB due to inrush you will find you switch has a short life...

 

[sajeel]

Good pointers people am will look into type c mcb, to be honest have not taken tranny to friends house yet might not even trip, just tested at his home

 

[Steviec1]

Type D are rare as few loads need them, and for higher current type D MCBs it can be hard to meet the 0.4s disconnection time for final circuits (you need quite a low Zs to hit the magnetic trip to meet that specification).

They tend to be for protecting sub-mains (when 5s on the thermal part is OK), but are not as good as fuses there in terms of selectivity with downs stream MCB/RCBO. Or for high inrush things like big transformers and motors, again not a common domestic type of load.

Also if you are regularly switching a load that needs a type D MCB due to inrush you will find you switch has a

Good pointers people am will look into type c mcb, to be honest have not taken tranny to friends house yet might not even trip, just tested at his home

Schneider produce d type breakers 1 pole up to 60A din rail mount.
I have one of these

 

[Steviec1]

Schneider produce d type breakers 1 pole up to 60A din rail mount.
I have one of these

They will also supply 32A