This is the call Glenn gets most, so here's the straight answer.
Fuse carriers and circuit breakers don't share a fitting. The board was built around fuse holders. No rail for breakers, no spare room, nothing an RCD can clip into.
So there's no halfway option. You can't add a couple of breakers or retrofit a safety switch. The enclosure comes off and a new one goes on.
The upside is you only do it once. The new board goes in with spare ways, so the next air conditioner, ensuite or charger is a small job rather than another full day.





