The trip switch on the consumer unit that takes away all your electrics is a safety device - it has detected an unsafe condition in the washing machine - power is leaking to earth - the trip prevents electric shock hazard just in case the power may be leaking through a person.
Stop using the washer and either replace it or have an appliance engineer look at it - it may be a simple fault - you do not say the make, model or exactly at which point the trip happens - the engineer will take note of when the trip trips to aid his diagnosis i.e. if you get the trip before the heater comes on (is due to come on) or before the motor starts then it will be neither of these.
Good luck...
Peccavi, October 2010
