That's the same as light switches here: down=on.
As you can see from the pics above, circuit breakers are up=on. Main switches have changed over the years: The pre-war side-handle types were up=on. Then the post-WWII consumer units went to down=on. Now with the use of circuit-breakers becoming more common, the main switches are changing back to up=on, as above.
I find the American approach of up=on for everything far more logical. And although I grew up with light switches being down for on, having gotten used to it the other way in the States, I prefer up=on.
