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Is My System Toast?

The electricity in my town went out the other day for a short time. My wife was in the living room where my stereo system is. The amp is a Bel Canto eVO2i and a pair of Quad 12L2 speakers. She told me that when the power came back on that the left speaker crackled and smoked a little. When I looked, it had a constant low but discernible hum. I tried the speakers and they were dead. I switched the amp input to my CD player (which had been completely powered down) and there was no sound. Are the speakers and amp pretty much gone? Is it worth having the amp looked at for possible repair?

masswineguy
jea48
4,908 posts
 

I agree on a whole house Type 2 SPD 

I use Tripp-Lite Ultra Type 3 point of use SPDs on the PC computer and Home theater system. Various other LED TVs I use Tripp-Lite Type 3 SPD power strips. 

(FYI,The branch circuit wiring length must be a minimum of 30ft to use a type 3 point of use SPD. That is now a requirement in the 2023 NEC. It has been a UL requirement for at least a few years. Impedance and inductance matters in the branch circuit wiring when using a plug in Type 3 point of use SPD.)

 The whole house Type 2  SPD must be installed per best practices.

The majority of high voltage transient surges in a home are caused by electrical appliances and electrical equipment found in the home.

For lightning protection a low resistance Grounding Electrode system is also needed. IEEE recommends 5 ohms or less for commercial and industrial facilities. 

NEC just says if the electrode to soil resistance "is measured" it shall be 25 ohms or less. Way to high... The lower the grounding electrode to soil resistance the quicker the high voltage lightning transient is diverted to Mother Earth. Simple Ohms Law.  

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tcutter's avatar
tcutter
439 posts
 

This got me thinking about my generator and what kind of surge protector they put on it. Turns out it is a "Type 1 Service entrance rated 100000 surge amp hybrid MOV/gas tube surge protector" in an "NEMA 6 enclosure". Or at least that's what's on the invoice. 
From Grok:

Type 1 SPD

  • Installed ahead of the main breaker, between the utility meter and your service panel.
  • Designed to handle direct or nearby lightning strikes and utility switching surges.
  • Can often be installed without a dedicated breaker.
  • Highest exposure to incoming surges.

I guess they are available to mere mortals. Purchase price $170. 

jea48
4,908 posts
 

AI says:

AI Overview
 
Overvoltage Protection: Causes, Types and SPD Response

A gas tube surge protector (Gas Discharge Tube or GDT) will not protect against a temporary, sustained, over voltage. GDTs are designed to handle brief, high-energy transients (like lightning strikes) by creating a temporary short-circuit to ground, which only extinguishes when the voltage returns to normal. [1, 2, 3, 4, 5]

I don't have time tonight. I will research further tomorrow afternoon.

Notice that word transients. Transients are not temporary, sustained, overvoltages.   

As for this: 

Designed to handle direct or nearby lightning strikes and utility switching surges.

Direct lightning strikes?

How about the warranty coverage? What does it pay for? 

 

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