Any transformer will experience a high inrush current at switch on and the bigger the transformer the bigger the inrush. Almost all isolated supply will be protected by an MCB with a type B rating. Ideally, if large inductive loads are being used, a type C rating would be expected.
The problem is even if the transformer is fitted with in-rush protection this is usually via a NTC (high resistance when cold and low resistance when hot). So once the unit is powered on the NTC has a low resistance and is effectively bypassed. If now the equipment is quickly turned off and on then the in-rush protector resistance will be low so a high current will occur. This can happen when plugging equipment in or out, as the contacts in the plug may make and break rapidly. Remember it can take a few minutes for the NTC to cool fully and restore its effectiveness.
The same applies for most switch mode power supplies so these can also be a new source of problems!
