Hello LG.
I have a questing about how polarisation of the power supply voltage affects HID ballasts with electronic ignitors. Schematics on ballasts and ignitors always show which wire should be neutral and which wire should be live. But if I want to power one through a wall socket (or even hardwired, color codes are apparently unrealiable here after the main distribution board from what I have heard), which wire ends up as neutral and live is random because the sockets and plugs used in my area are unpolarised. So every time I have tested a lamp with a ballast that has an electronic ignitor, I have always measured polarity of the outlet and plug so it is correct before connecting the ballast. This is obviosly inconvenient, since it may differ between different outlets and if an extension cord is used.

So my question is, can live and neutral be swapped for a magnetic HID ballast with an electronic ignitor without causing harm to anything?

Thank you.

Yes, because since it is AC, it should not matter. The only difference would be the danger posed from touching the bulb socket or something.

If you think about it, plenty of ballasts can run on 240V where both leads are live (in much of the US, anyway).

The main reason is, then (unlike EU incandescent) large HID sockets do not keep the lamp shell disconnected when it is possible to touch it. So connecting it at neutral is a means of reducing risk of electric shock when changing bulbs. So such connection is considered as "safe practice" on fixtures, what are not possible to totally disconnect - nearly all fixed installation (only phase is switched OFF and even this is not as reliable - wrong CB,...).
On portable fixtures with wall plugs the safe practice is unplug them form the wall socket before servicing, so then the phase and neutral polarity does not matter anymore...

Okay, I don't need to worry about that anymore then. Thanks.