Hello Guys
A little help here, I know what I need but in achieving it is my problem. I need a whole house TVSS which have a 120V load side which I would connect to a shunt trip main plug in breaker.

My client need his house to be protected from surge but if the surge protector fail he need the power off.

This would similar to smoke detector and elevator shunt trio breaker.

all help welcome.

Larry

Interesting customer. I can't think of any particular brand but if you find one with a dry contact rated for the voltage that closes on alarm and replace the main with a shunt breaker that be the simplist I think being a red application, industrial grade stuff may be out of their price range

I have never seen a residential smoke alarm that has a relay in it but you may be able to find a multistation one that you could hack a relay into on the remote circuit. It might be worth talking to Kidde or one of the other manufacturers to see if they offer such a relay unit

Hello Greg / Sparky
Thanks for your post, in short what I am looking is a whole house surge protector that is able to operate the shunt trip main breaker which we will install.I am not sure if there is anything like that on the market.

Larry

So your customer wants a whole house surge protector which will shut off power if "X" happens.

What is "X"?

Failure of surge protector?
Surge is above a certain value?
Difference between voltages of phases?
Over voltage? Under voltage?

In the industrial control world there are devices that have contacts that operate when certain conditions are met. For example, under/over voltage relays and TVS units that signal when a module has failed.

Do they want the power to be switched off and stay off? That could lead to some unpleasant consequences. Flooded basements, frozen pipes, thawed freezer, warm refrigerator, triggered alarm systems, etc.

You might want to go back to the customer and find out exactly what they are trying to protect. Point of use protection might make more sense.

Another Larry

I am confused. The surge has already come and gone, taking what it could with it. Why drop power then?
These things are measured in microseconds if not nanoseconds. You are never going to get a shunt trip to go that fast.

Sorry about the "alarm" thing.

OK, a quick look in the WW Grainger catalog (Book)
Page 272, Vol 407

Item 13W846, single phase 120v
Item 13W847, 3 phase

Both have audible alarm, dry contacts, etc.

Pricing is not avail in Catalog, go on WWG.com

They should ship to Cayman

Good call John. I also agree with Larry too. We are not sure what the customer wants the config. I'm not abvocating don't install it or sell what you can sell. What I am saying it what like Larry is saying that you may not get what the customer is invisioning he/she's is going to happen on the next surge. I'd get the data, explain it like Larry explained, and if the custom still wants it, hook em up but put it in the bill that if you don't think it will work like your customer thinks it will, put on the bill that your not liable if it don't work like the customer thinks it will. The customer is not always right. Especially when it comes to electricty

I agree with all the comments from you guys 100%, as I am not 'big' on solutions that have limited information provided.

Clients (customers) may have high expectations on what they 'think' they want installed, but more than likely have no insight into a proposed method.

The issues of liability, and the proliferation of litigation here require very careful, professionally prepared documentation.

I can't imagine tripping the main for a loss of surge protection. I would definitely consider it upon detection of a lifted Neutral. Alarming on a loss of surge protection is a good idea.
Joe

What is this homeowner trying to protect against? I gather what he's really looking for is a 59 relay (overvoltage protection). You can set it to match the CBEMA curve and give way better protection than triggering a shunt-trip from an SPD that's designed only to protect against a particular type of transient condition. They're not cheap, though; I'm not sure how much they cost because I've never specced one one individually; I usually buy combo relays that cost $1000 or more.

Your other option is to bus-tap the SPD directly to the panel busbars. Since an activated SPD is a dead short, this will cause the main breaker to trip on any significant transient, no shunt trip feature necessary. I would imagine any Type 1 SPD should be safe in this application, but check the rating to make sure it doesn't require a 15A breaker or something.

I spec industrial-grade SPD on every project I do, and even put a consumer-grade whole house surge protector on my own home for $25 a few years ago, the basic SquareD 240V 3W model. [I put mine on a 30A 2P breaker.] Cheap peace of mind and yet another "best practice" that should be in every home but is rare because of nickle-diming...

If you have decent surge protection and a significant level of redundancy, transient damage will be rare if not non existent. It goes far deeper than simply hanging an SPD on the mains tho.

I'll take a 'back seat' on the spec part, and on what I feel is Greg's expertise.

I can't visualize using a SPD across the buss that would create a dead short to trip a 100 or 200 amp main. My gut leans toward the dry contacts and the shunt trip main, IF that's what the client wants.

SPD/TVSS don't "stop" transients, they work through voltage drop. The more current that's flowing through the wire, the greater the voltage drop, and the smaller the voltages experienced by the circuit(s) the SPD is protecting. Consequently, fault currents can be pretty high when they activate, 20kA or more. Plenty to trip a 200A breaker if the surge is that high. You want redundancy, you want SPD on the main panel, on the sub panels, and on power strips at the equipment. Damage from transients is pretty rare when the protections are designed right.

And yeah, 20kA+ is a LOT of current for a small device. The MOVs inside them can be damaged by high energy transients. Some of the really high end SPD include monitoring and will work through many small events or a few large ones and tell you when they're degraded and need to be replaced.

To the original point, you can get a number of high-end SPDs that have alarm contacts in them, and those alarm contacts could certainly be wired to a Shunt Trip on the Main CB so that if the SPD ever did fail, the contacts would trip the Main CB. But the big problem I see with this is that on all the ones I have seen, the alarm contact ALSO changes state when the power fails. Now technically, if the power fails, you also lose the power necessary for the Shunt Trip coil to function. But because of the way that works, I'm not sure you could ever energize the breaker in the first place. That's because the Main CB feeds the panel, which then feeds the SPD. So the alarm contact on the SPD will remain in the tripped state until it says "Ready", which means power is applied to the SPD. But that means the Main CB must close first, and any delay in the SPD alarm changing state means the Shut Trip will shut the Main CB off again immediately. You could get around this with a push button that opens the ST coil circuit I suppose, but then EVERY time the user wants to re-energize after a power failure, someone has to stand there and hold the button down to bypass the SPD shunt trip circuit, then energize the Main CB, then let go of the button AFTER the green "OK" light on the SPD comes on. That won't happen right on a dark and stormy night at 3AM...

I suppose that could also be done via a timer that delays every time power is energized, but the whole thing is getting a little ridiculous.