Surge on community center with flat

[grandfortune]

Hi all, got a community center job and the want surge protection, 3ohase in phase for community center and phase for the flat upstairs, question is, do fit surge at the incomming covering both installs or fotfor community center and inenfornflne for the flat ?

 

[MDJ]

usually a surge device is best fitted next to the distribution board it is protecting, if you have 2 different boards fit 2 units, unless of course the main board is supplying the smaller one and then one device would be adequate, however a picture posted up on here may suggest a better way is the way forward, admittedly this was 9 months ago and an old thread but if the OP is still around it would be interesting to see what was actually done.