How can you tell if you have fried a unit?

ive jus ordered a unit off the net form american and as i live in the uk i had a little us to uk plug adaptors and put it on, but i then read the back of the unit and it said 117v.. whereas i turned it on using a 240v plug, im jus worried that i have fried it or summin, i mean it didnt make any bang or hissing etc when i plugged it in, jus nothing.. will it still work if i bought a transformer to 117v?

but i wanna know if when somethings blown or fried would i of heard a bang or hiss or anything because it didnt do anything. im hoping its still alright as ive jus ordered a power converter for itHow can you tell if you have fried a unit?
You may have fried the unit. You can look it over and see if there's a fuse that's blown. It may not be installed so it's accessible from outside the unit. You may have to take the cover off and look for a fuse. If you didn't hear any sizzle or bang or especially if you didn't smell any burning odor you may be OK. Look for the fuse and hope for the best.
I think it's dead. Check the fuses by all means but I guess it's a safe bet the mains transformer will be dead. This is the bit that takes the incoming mains voltage (110v US and 240v UK) and drops it to the voltage required for the internal electronics.Sometimes there is a selector switch on the back for you to select the input voltage.How can you tell if you have fried a unit?
it depend if the unit you plugged in has an internal fuse this may have

blown if so remove the back and look make sure its unplugged first

if it has a fuse and its blown you may be ok if not check transformer

see if its melted or burnt check board for damage if so bin itHow can you tell if you have fried a unit?
If After you connect it to a transformer it does not turn on, then it is probably fried.
Most times you won't hear anything. A piece of wire melts in the fuse and everything shuts down...if it ever started.

If you're lucky that's all it is.

Check the plug fuse. Putting 240v through a 117v circuit pumps a lot more amperage through it so it may have blown the mains fuse.

Then check the unit for a voltage change switch and switch to 220/240v if it has one.

Plug in.

If it doesn't work it may have blown the internal fuse in the unit.

Take the back off, replace the fuse if it's blown, and try again.

If it still doesn't work, you've blown the circuit somewhere.

Bin it,or if you're any good at circuit repairs, have a go.

If there is no voltage change switch then as you say, get a transformer.

It must be rated for at least the power usage of the unit and preferably twice that for cool running.....20w for a 10w unit.

Remember that USA runs on 60Hz and we are on 50Hz., which will affect frequency-dependant motors. They will run slower here if no frequency change is suppplied in the change over switching circuit on the unit, or in the transformer.

Careful therefore with units having cooling fans inside, and get a good air path into them and plenty of ventilation.

Best of luck.