Hi inch, sorry missed your post I'm still posting in a confusing manner elsewhere. A pic would be interesting, if it's no trouble otherwise don't worry, cheers Joe.
Here it is, main consumer unit which is full is in the top right corner, the auxillary CU has two trips, one is a slow (cat c or d can't remember) trip for the compressor on start up. The other trip is for an outside socket. Think it's fairly self explanatory, in any case i'm probably not the best person to ask