I actually have a similar 'concealed' Belkin surge protector to the one you mentioned connected to my UPS. It's fine, just make sure that you replace it before the little light on it's side goes out. This is true of any cheap surge protector.

Trevor

If i did get the one i mentioned earlier, would it be ok if i plugged my fan & shredder into it as well as the iMac, or is it advised to keep them on a different strip.

I would keep them on a different strip which is plugged into a different electrical circuit altogether.

Trevor

Could you define what you mean by "different circuit"? Do you mean on a different strip plugged into a different socket, or different room, or different floor, or different building, or different country or...

An easy way to think of a single 'circuit' (at least the way I'm using the term) is to look at your circuit breakers (or your fuse box if that's what you have). All the outlets served by one circuit breaker (or fuse) is known as one circuit.

How many circuits are served by one circuit breaker is variable. Some times two outlets side by side are served by different circuit breakers, sometimes you have to go to a different floor to find a different circuit.

Trevor

The Fan and shredder have to be in the same room as the iMac, and there are only 2 outlets in the room (one double socket, one single). Doing what you said seems like it would be a hassle, our house is quite old (about 100 years), if that makes any difference in how many breakers there are.

What damage do these things do anyway? If they make small surges, then would a surge protector stop them getting to a iMac if both are on the same strip? The fan is a 50Hz, 45W and the shredder is 50Hz, 1.0A

I never knew the cause of the flickering on mine; thought the light itself was crapping out -- now I'll run out and buy a new one. Thanks, Trevor.

Definitely listen to cpragman. Generally, don't put computers that store data on the same circuit as machines that have (relatively big) brush motors such as vacuums cleaners, fans, shredders, hair dryers etc. The brush motors cause a lot of noise on the entire circuit. Simply moving to another outlet is not enough - you must ensure that you are on another circuit breaker.

A possible remedy - Lighting and plug-in outlets are usually on different circuits. Though, it's best to check with a licensed electrician. So, one fix could be to have an outlet installed on the same circuit as your lighting. Plug your "dirty" or noisy appliances such as your fan, shredder, vacuum into this "lighting" outlet. I suggest setting this outlet at counter height to indicate that it is not associated with the same circuit as the other outlets. Again, there are many configurations for wiring and wiring done wrong - so check with a licensed electrician and explain your needs.

Disclaimer: I am a Computer Manufacturing Engineer / not an electrician.

I think this is a bit draconian for Macs which in my 20 years experience have very good power supplies that ignore most of the spiking caused by universal motors (eg Vacuum Cleaners and Shredders). Perhaps I'm just lucky, but I've never had a problem caused by a power glitch.

Well the iMac, shredder and fan have to be in the same room, and there is only 1 fuse for the entire floor, and getting a socket fitted on the lighting circuit isn't exactly possible. There is 1 other floor in this house, but i couldn't move the room's contents there because:
A)No room
B)there is carpet, so a vacuum cleaner would have to be run(alongside the fridge and electric shower that are already there) hence making moving pointless anyway.

Of course, you're welcome to use any set up that you want, but my advice is that if you can't put the shredder and fan on a separate circuit, I'd at least advise that you use a UPS (rather than just a surge protector). This is the same thing I recommended way back in post #2 of this thread.

Trevor

I'm slightly confused, if the fan & friends make small surges/electrical noise, wouldn't a surge protector cancel out those surges/noise, if yes, then wouldn't plugging them into a different outlet (as opposed to on the surge protector) do the job?

A different outlet will do the job if it's on a different circuit. Otherwise, it's all connected behind the scenes, so there's for all intents and purposes no isolation between different outlets.

A surge protector should help with small surges, but I don't think it does anything for noise. A good* UPS should isolate the source voltage from the output voltage by connecting the output voltage to the battery.

*I think that some cheap UPSs may not do this, actually, and the battery only gets involved when there is a power outage.

Which is why a different circuit is best for isolating known sources of noise on the electrical lines internal to your house, but if there's no way to do that, a UPS might be an adequate workaround. And a UPS has other advantages too, such as protection from powerouts.

Trevor

What damage does this noise do anyway?

That's a matter of debate. Possibly nothing, possibly a lot. It depends at least partly on how good the power supply that you have is at dealing with noise. Some computers live in a noisy environment and may never have a problem. Others crash every time someone turns on a hairdryer.

Trevor

Do the ones that crash every time someone turns on a hairdryer happen to run Windows :D

i think i'll just risk it and use the surge protector i mentioned earlier.