Neff 1422 Oven ?

Recently noticed only part of grill element was working and the same day it Tripped the Electricity supply when my partner was cooking.
On inspection I saw grill element had melted in one area and so obtained new one from local source.
No problem fitting new element and ensured everything was put back safely and correctly.
The new element worked for approx 20-30 seconds before supply was tripped again. I can switch cooker on and use the hotplates but as soon as oven or grill is switched on the power is tripped!! All wiring seems ok, so what is causing malfunction.
Would be very grateful for any help on this problem.
Thanks
Tony.