I was tired and distracted and made a mistake withno consequence.
I’ve never had any 230v electronics before and I received an external hard drive that I knew had a 230v power supply. And without thinking I plugged it into 110v and it worked fine.
After realizing my error I opened the power supply and found that it had a wire that you could change connections for 110v which I did.
Good thing I'm not in a position to do it the other way around.
... because the "other way around" could have been fatal for that device.
It is however not surprising that it did work with 110V ... it may have a switchmode power supply in it which can work over a wide range of input voltages, and what typically happens if it's set to 230V but only gets 110V, it just can't deliver its full maximum output power, but may still work fine with lighter load currents.
At least this is what I found out with some 230V based PCs. They worked fine at 110V until I plugged in the hard drives and a power hog graphics card ... and then the power supply could not deliver the required power anymore and it failed to boot.
- Uncle Bernie
Most recent computer power supplies use APFC (active power-factor correction) and automatically adapt to a wide voltage range, from 90–270 V. But checking the specs on every device is good practice (or at least those without fixed power cords).