Whole House Surge Protection

[shoon]

Anyone have any knowledge around whole house circuit protection? Is it worthwhile insurance?
From what I've read whole house circuit protection paired with surge suppressing power bars at the appliance end is the best form or surge protection. I understand the theory on how surge suppression works- MOV's 'clamp' when voltage exceeds a rated threshold and 'dumps' the excess energy to neutral / ground. However I'm still a bit fuzzy on ideal location for protection.

Next question would be on the best location to set it up.
I have a 200 Amp main service to garage, and 100 amp sub to house 100' away. Should it be installed at the 200 AMP main panel or within the 100A sub panel?
Or does it depend on other variables ? ie; if a lightning strike is in closer proximity to house than garage it would be advantageous to install it at the 100 amp house panel?

I live in a fairly small town with older hydro infrastructure. Brownouts and other issues like extreme wind and phase to phase faults on transmission side are very common. Just recently a brownout wiped out a bunch of electronics for a bunch of my neighbors.

 

[GoldDigger]

Anyone have any knowledge around whole house circuit protection? Is it worthwhile insurance?
From what I've read whole house circuit protection paired with surge suppressing power bars at the appliance end is the best form or surge protection. I understand the theory on how surge suppression works- MOV's 'clamp' when voltage exceeds a rated threshold and 'dumps' the excess energy to neutral / ground. However I'm still a bit fuzzy on ideal location for protection.

Next question would be on the best location to set it up.
I have a 200 Amp main service to garage, and 100 amp sub to house 100' away. Should it be installed at the 200 AMP main panel or within the 100A sub panel?
Or does it depend on other variables ? ie; if a lightning strike is in closer proximity to house than garage it would be advantageous to install it at the 100 amp house panel?

I live in a fairly small town with older hydro infrastructure. Brownouts and other issues like extreme wind and phase to phase faults on transmission side are very common. Just recently a brownout wiped out a bunch of electronics for a bunch of my neighbors.

1. The MOV or other protective device dumps enough current to neutral or ground that the impedance of the source and wiring pulls the voltage down to the threshold of the device. As for the energy, that unfortunately cannot be dumped, it has to be dissipated in the SPD itself for as long as it can last.
That is one reason that they may only be good for one protective event before needing replacement.
If the OV is minor, then the SPD may survive to protect again.
2. SPDs will do nothing to protect against brownouts (low service voltage) or loss of one phase to equipment.
Nor can they do anything about sustained overvoltages such as from a primary line dropping onto a secondary, or a compromised neutral.
The best you can hope for in those cases is that they clamp the voltage while OCPD is opening or the short is burning out.
3. A phase to phase swinging fault on overhead wires is usually a brief event and SPD may be able to mitigate damage. But don't count on it.

For brownout and phase loss, the only reliable protection is electronic monitoring that disconnects you completely from the service when the voltage goes way out of tolerance.

 

[al hildenbrand]

. . . I'm still a bit fuzzy on ideal location for protection.

Next question would be on the best location to set it up.
I have a 200 Amp main service to garage, and 100 amp sub to house 100' away. Should it be installed at the 200 AMP main panel or within the 100A sub panel?
Or does it depend on other variables ? ie; if a lightning strike is in closer proximity to house than garage it would be advantageous to install it at the 100 amp house panel?

You are correct that a "layered" approach is good. The whole house unit takes a lot of the energy off the top, and then the point-of-use surge protective devices (SPD) clamp down further on the remaining surge.

The subjective part of your question pertains to the best locations. To work towards an answer, figure out what you value the continued operation of the most. It's about lifestyle. Anything that is solid state controlled is vulnerable to surges. Maybe you value, above all else, the microwave timer so you will have a hot cup of coffee in the AM. Or maybe the solid state workings of the variable air volume furnace is important. Or maybe it's the garage door opener remote control receiver because of transferring little tykes being easier inside.

Any way, you get the idea. Make a list, and be sure to get the odd stuff, not just the computer and the TV. If none of it is in the garage, don't worry about the garage. If there's stuff in both the house and the garage, do both panels. Make room in the panel to connect the whole house unit so that the leads can be kept as short as possible and run as directly as possible with little or no bending as the leads go to their terminations (this significantly reduces the impedance that the high speed transients encounter, improving the performance of the SPD).

Then add point-of-use SPDs as needed at each utilization equipment.

And the most valued lifestyle item(s) might require (at your discretion) a battery standby power supply or even an actual uninterruptable power supply sized to the length of power outage that you can afford to buy batteries, or a motor / generator for. Maybe something like the internet router / wifi equipment and battery charging of phones, laptops, etc.

 

[Coppersmith]

Surge suppressors protect everything downstream of the device, therefore the best place to put it is as close to the service point as possible. Our local code requires a surge suppressor be installed either in the meter can or the main panel. (Tampa is a heavy lightning strike area.) Even washers and dryers can be damaged by a surge.

Most surge suppressor devices come with a guarantee to replace damaged stuff if the surge device fails to protect. I've seen them as high at $50,000. Not sure how many hoops you have to jump through to make a claim, but it's definitely a selling point for my clients.

 

[Little Bill]

Surge suppressors protect everything downstream of the device, therefore the best place to put it is as close to the service point as possible. Our local code requires a surge suppressor be installed either in the meter can or the main panel. (Tampa is a heavy lightning strike area.) Even washers and dryers can be damaged by a surge.

Most surge suppressor devices come with a guarantee to replace damaged stuff if the surge device fails to protect. I've seen them as high at $50,000. Not sure how many hoops you have to jump through to make a claim, but it's definitely a selling point for my clients.

Most that I've seen/read do not cover the newer TVs for some reason. That is one item that would go to the top of my list.

 

[brantmacga]

Most surge suppressor devices come with a guarantee to replace damaged stuff if the surge device fails to protect. I've seen them as high at $50,000. Not sure how many hoops you have to jump through to make a claim, but it's definitely a selling point for my clients.

Wanted to add that most all whole-home surge suppressors I've sold also require surge protection at each electronic device (TV's etc....) for warranty claims.

In new houses, I use square D surge-breakers in the panel coupled with P&S tvss receptacles at every tv location.



Sent from my iPhone using Tapatalk

 

[1haz]

Wanted to add that most all whole-home surge suppressors I've sold also require surge protection at each electronic device (TV's etc....) for warranty claims.

In new houses, I use square D surge-breakers in the panel coupled with P&S tvss receptacles at every tv location.



Sent from my iPhone using Tapatalk

As inexpensive as they are such as SQ D, Intermatic and the ones I use Sycom, I would recommend putting one in the main panel and one in the sub- panel. Then at tv's and computers I use what Sycom calls a point of use device. That way the electronics are also covered by the replacement warranty. The point of use protects your electronics from any thing that may get by the panel protectors and protects you from the phone/cable which is where most of the tv's get damaged from. The phone and cable lines are not grounded as good as your service and here in FL I find more surges coming thru the phone/cable than the electric service.