[sdflhasjd]

This thread looks like a relevant one to mention an issue with the Mac Studio that causes large inrush currents when you plug it in. The power connector arcs badly enough to trip a domestic 30mA RCD, it's reproducable with several units and on different electrical circuits at both home and office.

[mschuster91]

The arcs have nothing to do with tripping the RCD part of your breaker. The RCD part only trips on a substantial current (>30 mA, or less for specialty devices, or more for upstream RCDs) between hot and ground, it doesn't care at all about the current flowing between hot and neutral.

That inrush current however, given sufficiently large buffer capacitors, can be enough to trip the overcurrent protection that most if not all RCDs also have - and that one tends to get more sensitive as they age, it's a common issue with old breakers.

(Another device that could trip is an arc-fault detection device, but AFDDs are fairly new and not required by many electrical codes. Nevertheless, it's a good idea to upgrade your distribution boxes with them, if you have the budget. These things save lives.)

[scq]

That is not how an RCD works. It doesn't even look at ground.

An RCD will trip when the difference between the current going down the live and neutral conductors exceeds a certain value -- in normal operation they are opposite and cancel each other out.

If it operated how you describe, it could never detect someone touching a live conductor, because the current would not return through the ground prong.

[sdflhasjd]

The Mac Studio has a 3-pin earthed C5 connector. I presumed it's not overcurrent as it trips a 32A type C RCBO in an instant.

Either way, it's certainly a problem with the computer - I've far more demanding equipment that has never done this, and have yet to find a circuit it won't *pop*.

[MilaM]

I noticed exactly the same thing on a new Mac mini M2 base model when I conncted the power cord. Now I'm relieved that it seems to be a common problem.

I don't know anything about electronics. Do you think this is some kind of defect or bad design of the power supply?

[tuetuopay]

Apple is very generous on input capacitors for their power supplies. It's usually a sign a good design as it's one of the first places companies skimp; and ensures that even dirty wall power or highly spiky load will not trip the PSU and keep the computer fed. However, it is widely recognized that Apple overdid it on apple silicon macs. Like, they really should have skimped a bit on that one. (we have racks full of M1s at work, and boy powering the rack on is a pain due to the inrush)

[fsh]

Using too large input filtering capacitors without a soft-start circuit is a sign of very poor circuit design.

[ComputerGuru]

What size are the capacitors?