A1200/500 PSU, to ground or not to ground...

[José]

So I'm putting back my Amigas to work again a bit and am in the process of replacing a plug on a good old A500 psu that I'm using in my A1200. The original plug did not have the ground connected though the wire is there and we all know the A1200/500 PSU connectors have ground.
So what are the (dis)advantages of connecting ground ? Are the A1200/500 double insulated ?

[Daedalus]

The computers themselves aren't double insulated, no. The power supplies should isolate the potentials the computer uses, but it's always a good idea to ground them. In the UK and other countries with a mandatory 3-pin plug, Amigas have their shield grounded all the time. It will work fine without it, but it probably helps reduce noise in the audio and video circuits, as well as protecting you in case anything in the PSU fails and lets mains electricity flow into the computer.

[idrougge]

I've never seen an ungrounded Amiga PSU. Is it some Portuguese problem?

[zipper]

I think upto 90's ungrounded wall sockets were used here in dry rooms - so excluding kitchens, WCs, washrooms. So all Amigas were sold with ungrounded plugs. And the power supplies were surely double insulated.

[Daedalus]

Yep, the power supplies should be double insulated, but the ones I have anyway do not bear the standard double insulated mark. Also, any European Amiga PSUs I've seen were fitted with Schuko plugs, which do provide grounding contacts but also fit ungrounded sockets fine. US 110V PSUs I've seen also have grounded plugs. But of course there were many, many variants of power supply so it's quite possible there were different designs that I've not come across.

As for ungrounded sockets, even today they still seem to be relatively common in the US and some parts of Europe. Hotels I've been in in Spain and Portugal have both had a mixture of grounded and ungrounded outlets.