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I want surge protection, but I have no grounds

Hello all, this is my first post.

I am seeking advice on how I should handle a problem with my apartment. I recently upgraded my CD player and have suddenly become concerned about surge protection. Unfortunately, I can't use a surge protector effectively because I have no grounds in my apartment - only 2-prongers.

I read that I could use the grounded adapter plugs to solve this problem. After installing one, my multimeter reads 123V between the hot and neutral, and only 35V between the hot and ground... I believe this means the boxes and conduit are not metal and cannot serve as a ground. I tried again on 3 other outlets with the same results on every attempt.

At this point, the only options I can think of are:

1) Don't worry about it. Surge protection is overrated? One thing I can say is that about a year ago lightning struck a transformer outside the apartments and blew the video card and modem on my computer (no stereo damage fortunately).

2) Rig something up. I heard this was not very smart, but I could run a wire from the ground on the adapter to the drain on my kitchen sink. Hopefully that would give me a solid ground connection, and wouldn't electrocute me in the shower one day.

3) Buy a ground electrode and put it outside my window. Unfortunately, I don't even know what these look like, how much they cost, how hard they are to install, or if the owner would freak out if they found it (I live on second floor).

4) Suggestions? Is there a product or option I haven't heard about? My budget is limited... but spending a little now is better than replacing my entire system later.

Thanks for any help offered,
Will
wtwood
tbg
5,263 posts
 
Have you read a review? All it seems to be doing is surge protection and some filtering. It may be that your present sound is better.
nealhood
199 posts
 
MOV based surge arrestors don't merely divert current to the ground and neutral conductors (circuits). They dissipate the energy of the surge pulse in the MOV assemblies. Now the ground or neutral conductors do carry current during these surges but, this should cause no concern assuming your house wiring is in accordance with the safety standards and codes designated by the NFPA. These shunt type MOV units often include a one or two stage RFI filter as standard also. And, they offer minimum series impedance, certainly an advantage when feeding a power amplifier.

Nevertheless, the brick wall filters are good also. But, I do question their ability to properly clamp a surge voltage on the hot conductor if no current flows into the gound. Normally surge pulses appear between hot and ground or, neutral and ground. If these units do not pass current to on the ground conductor then how do they limit the peak voltage appearing on the hot conductor during a hot to ground surge(especially slow rising surge)? Remember an inductor does not offer much impedance to a slow rising waveform - such as when your utility power merely fluctuates due to system instability/oscillations, etc. when the grid is subjected to disturbances such as blowing a throwout on the pole. Also, these inductor type filters generally exhibit a significant series impedance which may hinder the stiffness of a power amplifier. But this should not really be a major concern because supply impedance is often overplayed in the audio hyped marketplace.
wtwood OP
4 posts
 
I didn't realize that surges could be through the neutral, and I now see that it does not protect against them. Unfortunate. Do these occur with the same severity and frequency as hot line surges?

Regarding the supply impedance issue: I live in an apartment and rarely play the system at high levels. My receiver is rated 35Wx2. Does my modestly powered system make this less of a problem than if I had a big 5 channel system for instance? Does current have any relationship with impedance in this situation? Intuitively, I don't see why it would, but I don't really understand how the unit functions and if it behaves differently at different currents.
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