Hi,
Tests to isolate where the problem is.
Switch off the wall outlet and powerboard (if it has switches).
Remove the powerboard from the outlet and plug the TV directly into the wall outlet. Switch on wall outlet
Switch on the TV.
If safety blows:
Switch off the outlet, reset the safety switch, remove the TV from the outlet and plug another electrical appliance directly into the same power outlet and switch on e.g. an electric kitchen kettle. (make sure that it has enough water in it).
If safety blows
Wall outlet is the problem. Call an electrician
If safety doesn't blow:
Switch off outlet, plug in powerboard, plug kettle into powerboard and switch on.
If safety blows
Powerboard is the problem.
If it is the powerboard, replace it. Most powerboards are designed as 'sacrificial' and are irreparable.
If safety doesn't blow:
TV is the problem.
A safety switch operating indicates that there is a circuit path between the active line in the supply and earth which shouldn't be there.
It is designed to save a life by preventing appliances becoming 'live' on the exposed areas, which should be connected to earth if the unit is not double insulated.
If you do not know what to look for as far as electronic/electrical circuits are concerned, I strongly recommend that you leave it to the experts. Call a reputable, professional TV repair service and ask for a quote for a repair.