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Household Surge Protectors - Good or Bad?

A few weeks ago I had a surge protector installed in my breaker panel.

It was a new variey I had not seen before, in that it took the place of two standard sizede breakers and connected to both phases of the breaker panel supply

Since then we’ve had had a couple of power outtages and all the household devices kept running upon power restoraton - so far so good :-)

This past week I had reason to disconnect power and speaker cables to loan to a friend for audition.

Afterwards I reconnected the power cables to the amp and powered up.

NOTE: the system is on a dedicated line - it’s breaker was not touched by the install

Immediately I noticed a hum from the amp, where previously there had been none - even at full volume with the phono stage selected.

After lots of analysis and testing, I remembered the installation of the Surge protector.

I measured the impedance between the ground and the neutral and found around 5 ohms of resistance.

To temporarily get over the hum I have connected the neutral side of the inputs to a common earth tap on the power distribution box - it has worked like a charm - i.e. until I can get the electrician back here to fix the real issue.

So my question:
- Is this just sloppy work? - I’m assuming that the neutral of the dedicated line was disconnected and not reconnected correctly, OR
- do ALL housewide surge protectors such as the one I have had instlaled always present with this problem?

Thanks for any feedback

williewonka
elevick
2,636 posts
 
FYI-I have had a whole house surge for 15 years.  It only trips on very large spikes such as a transformer blowing at the pole.  Smaller spikes always get through.  Also, even with big spikes it is not nearly as sensitive as even the lower priced PS Audio stuff.  You should still use either a conditioner or surge at your system.  Several times I have had my PS blow while the whole house did not.  
There is nothing wrong with my whole house surge, it just wasn't designed for expensive audio.
dweller's avatar
dweller
3,735 posts
 
@erik_squires - Thanks for the sympathy. After giving it some thought, I think it was a whole-house GFI (ground fault interrupter) not a surge protector. It would pop open at least once a day.
erik_squires
15,647 posts
 
@dweller - Interesting. A whole house GFI sounds like a pain the butt! Any bad actor in the house could cause it. Individual GFI or now, arc detectors, however, save lives. :)

Best,

E
erik_squires
15,647 posts
 
FTR, there are all sorts of devices you can plug into an electric panel. I'm by no means an expert. I just happen to know what I think the OP is talking about. :) 

Best,

E
williewonka OP
3,066 posts
 
Thanks guys - the surge protector that is installed has an LED idicating it is operational. If there is an issue the LED goes out. There is no way to turn it off..

I'm pretty sure there is an issue with the neutral or ground conenctions, so I will take a look at them first.

I have had a similar hum with a consumer DVD player and my NAIM amp - it seems that NAIM has a particular design approach that seems to highlight grounding issues.

I've since installed a ground between the neutral side of the inputs and the ground of the mains supply - this made the amp completely silent (i.e. quieter than before the SP was installed) - BONUS :-)

I'll still check the neutral/ground, but I will then assess the need for the new grounding scheme.

One thing I did notice after the SP install - my home network/TV Streaming became much more reliable.

Many Thanks for all the input
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