Hi. Is it the trip switch (mcb, small switch) or the earth leakage protection (RCD, large switch which knocks out all the sockets in the house)?
If it is the RCD, then you may have a heating elementf fault. This is sitting in the base of your dishwasher and usually visible when you take out the trays. Check for visible damage.
Personally, I would recommend an appliance repair person as opposed to an electrician or plumber.
Reason being that they will normally carry such spares. An electrician will normally have to go and return with spares at your cost.