The circuit breaker that controls the downstair supply of lighting clicks off at strange times. The individual electrical items have their own breakers ie: lights, fridge freezer, TV and washing machine. The individual breakers do not click but the main breaker. It happens during the night when only a little power to run the fridge/freezer is used, but most days for the last 6 or 7 I wake up to no power downstairs. We have had 2 different electricians who have both tested the sockets and said there is no 'short' in the system.
The property is a 6 bed villa which has been completely rewired 2 years ago. The Electricians have not really found the problem. My freezer temperature is going up and down like a yoyo and when it happens during the day my lights are blown. It happened 9 times yesterday.
Any ideas.
I am more than happy to pay for a good Electrician who can solve the problem but who I have spoken to said it is either a 'short' which is difficult to detect or indeed just the 'circuit breaker' on the electrical board.
Thanks for your thoughts.
Happy New Year.

A loose connection at the breaker can cause heat, that will migrate into the breaker and cause trpping for no apparent reason.

Both the Line and Load side of the breaker needs to be checked for loose or corroded connection. This can be at the tab a plug in breaker plugs onto.

If this is elusive, a power recording meter may be needed, to record the amp draw over a period, and an infrared camera may be needed to find the loose connection that will show up as a hot spot.

I might suspect the fridge compressor, having a short to ground, try running a "temp" extension cord to a different location, not controlled by this panel... make sure it is heavy duty, and employing a ground..

If this trips, then the motor, is at fault...

Loose connections my first thought also. Could just be a bad Breaker. Is this 60 or 100 Amp Breaker? An Ampprobe can tell actual Amps being Drawn. Are you using Floor Heaters?