Voltage Question

Hi I just bought my first printer kit, the He3d H500. Got it from Gearbest. It said 110v U.S. plug, which it did come with, but it's wired onto a board that says 220.
Now I have an old dryer outlet on the other side of the wall from the room I intend to keep the printer. The plug says 250v on it and I tested to voltage to be actually 243v
I checked the breaker and low and behold there's a 240v 40amp fuse in there.
Would it be safe to utilize that line? Or is it to much for the printer and would fry it?

The Gearbest advertisement shows the US configuration as 120v and you've confirmed that the plug is US 110v. If you plug it into 220v (US typical) or higher, it's likely you'll let out the magic smoke. The Gearbest advertisement also notes that you should set the power supply to 120v. It is common for universal power supplies to have a 110/220v switch somewhere, and it is usually clearly marked. If you decide to change the plug to 220v, you would still have to check the switch to ensure that the seller hasn't already moved it to 110v for USA use. 110v/120v used interchangeably as well as 220v/240v.

Most power supplies are switchable - or will work on both voltages. Check the PSU and also that the cabling is suitable for 240V. If it's brown and blue and 0.75mm or larger, then it should be fine for 240V, but if it's black and white, then the insulation may not be suitable for 240V and it should be changed out.

I would fit a smaller breaker - or a fused outlet so that you have a local fuse or breaker at a value that will protect the cabling and appliance.

the psu will be switchable.