80Amp RCCB will trip after 5 min, but not 32A MCB; on reset RCCB retrips.Oven was not on. If Live & Neutral are reversed in plug, oven does not trip RCCB. If Neutral cut oven does not trip: if Earth cut oven trips after 5 min. Is it safe to use oven with the Live/Neutral wiring reversed? Will it overheat? Is there fault between Live and Earth? Why the delayed trip? Nigel Smith, london63@talktalk.net