Lets talk whole house surge protection

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  #1  
Old 03-30-11, 08:49 AM
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Lets talk whole house surge protection

I have point of use surge protectors on all my computers and electronics, but lately have considered adding a whole house surge protector.

There doesn't seem to be a whole lot of discussion on the boards about them though.

What brands/models have you used and liked?

I'm not crazy about the Cutler Hammer model from the big box stores, it just feels cheap.

Something like the Intermatic Panelguard or Leviton Panel Protector catch my eye with a better warranty than the Cutler Hammer one.

I assume all of these pretty much install the same way (need 2 20a breakers free)
 
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  #2  
Old 03-30-11, 09:27 AM
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Essentially yes, they all install the same. The difference is that some attach to an unused breaker and some are built in to a breaker so they don't sacrifice slots (Siemens brand). You also need to make sure that your grounding electrode system (rods, plumbing bond) is up-to-snuff to get good protection from any MOV surge protector.

There's not much to say about the various models. You can compare them based on warranty length, damage guarantees, Joule rating, clamping voltage, but you will pretty much find that units of similar price have similar specs.
 
  #3  
Old 03-30-11, 06:38 PM
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I think Intermatic dropped out of the surge protection market, but there are plenty of players left. Leviton makes some good ones, but I also like the ones that plug right on the bus in your residential main panel like ibpooks mentioned.
 

Last edited by CasualJoe; 03-30-11 at 08:07 PM.
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Old 03-30-11, 06:52 PM
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Not that it's needed, but I'd agree with everything Ben said. Personally, I'd recommend the $60-$80 models. I don't think it's worth the $200-$300 price tag on some models for a residential setting.

You're using point-of-use surge protection which is quite important. I find that panel surge protection is great for things like your microwave, fridge, oven, etc. Things with electronics that can't easily be connected to a surge strip.

When installing, make sure you keep the wires as short as possible. Every extra inch adds resistance that decreases the effectiveness.

For what it's worth, I have an Intermatic which seems to be working well. It was interesting though - the instructions called for it to be connected to a double-pole 30A breaker.

-Mike
 
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Old 03-30-11, 08:52 PM
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I have a Cutler Hammer CHSA. I paid about $50 at Home Depot, but it was a special order. I have a Cutler Hammer load center and I specifically chose this model over an external unit to keep the neutral lead as short as possible. Of course for all I know they just put a couple of LEDs in a 2-pole housing.
 
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Old 03-30-11, 09:08 PM
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Intermatic still makes whole house protectors however they were not available for MONTHS and are now double the price. Leviton also had some issues as all manufacturers had to meet new UL requirements and that always causes headaches. We had hospital surge strips on backorder with Levition for 4 months and Imtermatic was out of house surge units for almost as long. You would be lucky to find a decent whole house unit for less than 100 dollars. The breaker types are OK but they are SMALL so they do not have as much protection. What you need is layered protection. A good Intermatic whole house unit or Leviton, then surge receptacles and strips in conjunction. There is no way to ever totally eliminate some surges as lightning strikes are difficult to control as are severe utility problems. Use UPS units on all computers, those have voltage regulators built in as well as surge. I have even seen large homes install lightning protection to help. A 2 million dollar home locally had to do this as well as MULTIPLE surge units to protect 100,000 dollars worth of Lutron controls in the home as well as other electronics. Anyway, I have an Intermatic unit on my house and surge strips as well as UPS protection. I don't care much for the breakers because of the limited size of the units. Better than nothing I guess.
 
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Old 03-31-11, 09:50 AM
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Originally Posted by JimElectric View Post
to protect 100,000 dollars worth of Lutron controls
Did they just circle 10 of everything in the catalog?
 
  #8  
Old 03-31-11, 10:30 AM
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It my impression that these devices are gimmicks. The electrical department that installed these, from the company I worked for said they are not real surge protection. They have capacitors in them that store the electric for motors in your house on start up. Fridge, well pump, etc. It gives these appliances power from the caps on start up only. They advertise to save up to 25% off your electric bill. Thats a joke these electricians said.

They also said think about a surge from the main line. What is going to make the surge go into, and through a box tied in with breakers and back through the panel???

Make sense?

I am not a electrician but the union guys told me homeowners are wasting thier money on these devices. These devices do benifit commercial corps with large electrical equiptment and motors.

Mike NJ
 
  #9  
Old 03-31-11, 10:36 AM
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lawrosa, you're thinking of a different type of devices which are indeed a scam. Any of those that claim 25% power savings and similar claims are a scam.

Surge protectors are a legitimate product that do protect electronics from lightning and other types of surge damage. These are all made by big name brand electrical equipment companies. They have a component called MOV (metal-oxide varistor) that conducts surge current into your grounding electrode system where it dissipates into the earth. The ground rods do need to be installed properly and well bonded for the surge protector to function well.
 
  #10  
Old 03-31-11, 12:24 PM
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"Did they just circle 10 of everything in the catalog? "

LOL, actually I think the total was over 125K....it bascially was a large system that is beyond what most people would ever use....but with the money these folks have....well, you know..

Surge arrestors serve a big purpose, as stated. Some of the GOOD strips like a Leviton 5300PS or 5300HT actually have sine wave tracking. The cheapo units though offer little protection, usually they don't even start clamping until the voltage is high. Really a person needs lightning protection, top of the line whole house protection, and layered protection using surge receptacles, surge strips, and UPS systems. Most don't have ANY, but some have at least SOME. Even then though mother nature can surprise you...
 
  #11  
Old 03-31-11, 12:28 PM
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The biggest problem with surge suppression is you won't know if what you have is inadequate unless (until?) if fails. All the authorities on the subject recommend the multiple level approach with the whole-house at the service entrance and then less-expensive models at the point of use.

The second biggest problem is inherent with the MOV and that is that they can only "absorb" a certain number of surges before they fail. The size of the surge is a huge part of this and is why multiple levels of protection throughout the house are recommended. A whole-house model may be able to survive hundreds of smaller hits but only a few large ones before it fails. All whole-house models, at least all worth installing, will have indicator lights and these need to be checked on a regular basis to be certain the unit is still in some semblance of operable condition.

FWIW I installed the Cutler-Hammer Ultra in both my own home and in my sister's home. The price is somewhere around $150-$200 dollars and they require a double-pole, 15 ampere circuit breaker. I (we) may never need them but I sleep better.
 
  #12  
Old 03-31-11, 12:48 PM
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When you talk about breakers with built in protection, you're referring to the ones that only protect that one circuit right?

I definitely still believe in point of use protection, all of my computers, and even home entertainment system sit behind UPS's that do AVR.

I just like the idea of having a line of defense before them that protects the whole house. Washer/drier, furnace, fridge, etc etc..

I do need to fully investigate my grounding system, everything looks good but I want to get some resistance readings before hooking one of these puppies up.
 
  #13  
Old 03-31-11, 12:59 PM
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No, the breakers are supposed to protect the house panel and the house. All of the current companies make them for their panels and a lot of people like them. The only thing I dislike is the size as you can only fit so much protection into a breaker housing.
 
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Old 03-31-11, 01:09 PM
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Originally Posted by JimElectric View Post
No, the breakers are supposed to protect the house panel and the house. All of the current companies make them for their panels and a lot of people like them. The only thing I dislike is the size as you can only fit so much protection into a breaker housing.
link

Something like this is what your referring to? Thats a lot cleaner than mounting a separate box on the side of your panel.

When I saw surge breakers at the store, I always thought they only protected one circuit, ie using one for your office, and another for the living room.

Unless that's the case and there are both types.

Plus I just happen to have the first two spots available in my panel (FWIW it's a murray panel)
 
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Old 03-31-11, 01:20 PM
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Closer to the main the better. Yes, that is the type I was speaking of. I am pretty sure Siemans makes this too (Siemans owns Murray and the breakers are the same if it is a newer panel). But that one appears to be rated for use in them so you should be able to use it. Might check first though to be sure it is UL rated for Murray. And if doubt check for Murray or Siemans brand. IF, your panel is an older one that uses the multi colored breakers (old bryant breakers) the Cutler unit is fine regardless.
 
  #16  
Old 03-31-11, 02:10 PM
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I believe the Siemens surge units (QSA2020, QSA2020TVSS, etc) are listed only for use in Siemens brand panels, not Murray (even though they look the same). They do sell a stand-alone surge arrestor (part TPSA9040) that can connect to any mfr double-pole breaker.
 
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Old 03-31-11, 03:22 PM
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Is there a schematic on any of these products? I would like to see what componants are in there. I have a feeling they(the companys) will not show that.

I am curious to know how these actually work.

I have read about the capacitor based units that smooth out the electric, and heard some of those have surge protection also. They are the scam ones I was told. ( Save 25% off your electric )

But are'nt these the same type units?

Would'nt some type voltage regulator between the meter and the main be better? Something that supplys constant voltage, and if there was a spike it would reduce it or shut the main down? Something like generators have?

Or better yet like a giant surge strip. If you can plug your meter to one end and your panel to the other.

I know I am not a electrician but am just trying to understand.

Lightning struck a tree next door last yr and I lost a wii console (no video otherwise it works. I can here it) and a vcr (two different rooms). I have most everything else on some type of surge strips.

Just wondering.

Mike NJ
 
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Old 03-31-11, 03:44 PM
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Originally Posted by lawrosa View Post
Is there a schematic on any of these products? I would like to see what componants are in there. I have a feeling they(the companys) will not show that.
The diagrams are on the spec sheets. They are incredibly simple: a set of MOVs between the lines and ground.

I am curious to know how these actually work.
MOVs block current flow when the voltage is normal, but conduct current when the voltage is high. During a surge/spike, the voltage goes up and the MOV starts to short the lines to ground thus decreasing voltage and sending surge current into the earth. You can think of it like a pressure relief valve: closed when pressure is normal, opens as pressure gets too high.

I have read about the capacitor based units that smooth out the electric, and heard some of those have surge protection also. They are the scam ones I was told. ( Save 25% off your electric )
The actual function of the capacitor device is not a scam, but there is no financial benefit to residential customers because of the way power companies do billing. They fix a problem that residential customers are not penalized for having. Perhaps problem is too strong a word, more like inefficiency. In any case it doesn't matter in residential.

But are'nt these the same type units?
No.

Would'nt some type voltage regulator between the meter and the main be better?
Yes that is ideal for producing high quality power, but components in that size are very expensive, prone to damage and add inefficiency to the system. This is exactly how big UPS units work in commercial data centers where power quality is very important.

Or better yet like a giant surge strip. If you can plug your meter to one end and your panel to the other.
That is exactly how the panel mount surge protectors work.
 
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Old 03-31-11, 03:57 PM
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MOVs block current flow when the voltage is normal, but conduct current when the voltage is high. During a surge/spike, the voltage goes up and the MOV starts to short the lines to ground thus decreasing voltage and sending surge current into the earth.
That contradicting info. This is what I read from that Wiki site.

What varistors don't do

A MOV inside a TVSS device does not provide equipment with complete power protection. In particular, an MOV device provides no protection for the connected equipment from sustained over-voltages that may result in damage to that equipment as well as to the protector device.

A varistor provides no equipment protection from inrush current surges (during equipment startup), from overcurrent (created by a short circuit), or from voltage sags (also known as a brownout); it neither senses nor affects such events. Susceptibility of electronic equipment to these other power disturbances is defined by other aspects of the system design, either inside the equipment itself or externally by means such as a UPS, a voltage regulator or a surge protector with built-in overvoltage protection (which typically consists of a voltage-sensing circuit and a relay for disconnecting the AC input when the voltage reaches a danger threshold).


Im not sold yet. I am still trying to figure it out though.



Mike NJ
 
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Old 03-31-11, 04:03 PM
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It is not contradictory.

Originally Posted by lawrosa View Post
MOV device provides no protection for the connected equipment from sustained over-voltages that may result in damage to that equipment as well as to the protector device.
This is true. The MOV can only protect against short-term surges because it gets very hot while conducing surge current to ground. If the surge is "sustained" it will melt the MOV and ruin the surge protector, leaving the remaining duration of the surge to ruin the protected equipment.

A varistor provides no equipment protection from inrush current surges (during equipment startup), from overcurrent (created by a short circuit), or from voltage sags (also known as a brownout); it neither senses nor affects such events.
This is also true; the listed events are from too-low voltage. The MOV only protects against too-high voltage events.

Im not sold yet. I am still trying to figure it out though.
MOVs are not the ideal surge protection system, but they are cheap and plentiful and usually do a good-enough job. You could replace an entire household of typical appliances and electronics for the price of a full service-sized voltage regulator.
 
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Old 03-31-11, 04:12 PM
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OK one more question.

If lightning strikes outside and comes to the main panel what makes the surge go through this device to protect everything attached to the panel?

Don't electric flow to the point of least resistance?

If you say this device sends the surge to ground, isn't that what the panal will do naturally?

Mike NJ
 
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Old 03-31-11, 04:25 PM
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Originally Posted by lawrosa View Post
If lightning strikes outside and comes to the main panel what makes the surge go through this device to protect everything attached to the panel?
The normal voltage on the incoming line is about 120V. If lightning strikes the power grid outside and drives the voltage up to say 5000V. The MOV begins to conduct between the line and ground which rapidly drops the voltage on the incoming line; this creates a short circuit between the incoming line from the power company and the ground. Lightning is a very fast event, so once the surge has been dissipated to ground the voltage returns to normal and the MOV stops conducting.

Don't electric flow to the point of least resistance?
Current flows on all paths, inversely proportional to the resistance. It is more correct to say most, but not all, of the current flows on the path of least resistance. When the MOV activates it provides a very low resistance path to ground so most of the surge flows to the ground leaving only a small portion to go through your connected appliances.

If you say this device sends the surge to ground, isn't that what the panal will do naturally?
The normal path through the panel is out to the branch circuits where appliances are connected. Without the surge protector, 100% of the surge goes out through the appliances usually destroying them. With the surge protector, most of the surge will go straight to ground and only a small amount will go out through the appliances, hopefully saving them from damage.
 

Last edited by ibpooks; 04-01-11 at 09:52 AM. Reason: fix malformed quote tag
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Old 03-31-11, 05:02 PM
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Thanks very well written and informative.

I was not trying to dispute anything but am looking for something for my panal and assumed they are all a waste of money. I lost a wii console because of lightning and do not want to lose anything else.

My latest issue is the microwave trips its breaker ocassionally(dedicated 20 A). happens a split second becore it turns on. I am not sure if micro or breaker. Does not happen all the time.

I will start a thread when I get tired of resetting.

Mike NJ
 
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Old 03-31-11, 08:54 PM
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MOV's are a little miracle of modern engineering. As others have said, they are an inexpensive way of protecting from reasonably high-voltage, short-duration surges. The surge protectors are considered sacrificial as any decent spike will blow the MOVs but (hopefully) protect the connected equipment.

I will personally attest to how well they work. A number of years ago a telephone pole outside the house caught fire during a winter storm due to a fallen tree. The power was on until the pole burned through and dropped the transformer to the ground. The power went out, but as it went out, there was a significant surge. We had a few light bulbs with their bases melted and fused to the sockets. We also lost the circuit board to the oven (burn marks across it).

The surge protector on the computer (~$70) fried, but the computer was fine. There were MOVs installed in the garage door opener which fried. Replacement MOVs were about $10. Saved a $200 garage door opener.

After that, I have a whole house surge protector and high quality power strips or UPS on all the expensive electrical equipment.


As a side note - you need to make sure that other pathways into your house are protected as well. Telephone, CATV, etc. all need to have similar surge protection on them. It doesn't help to have a $400 UPS protecting your computer if a surge comes through your telephone line.
 
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Old 04-01-11, 01:14 AM
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The whole-house/panel surge protectors are intended to absorb the majority of the surge to the point that your surge strips at the computer/entertainment center/etc will be able to absorb the rest. We get some serious storms here, and last summer the power pole behind my house got struck by lightning. I don't have a panel suppressor, but everything is on TrippLite strips, and the computers are on APC UPS units. After the strike every single device indicated protection failure, and even with the protection I lost my PS3, a computer power supply, and one of my routers. I'm pretty sure that could've been avoided with a panel suppressor, because without it the individual strips took the full hit.
 
  #26  
Old 04-01-11, 06:21 AM
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Originally Posted by lawrosa View Post

What varistors don't do
This sounds like it was written by a Series Mode surge protector shill.

I'll knock the shills but not the series mode stuff. I haven't found anybody saying series mode protectors are inferior. They do appear to be better just based on how they work, but it's hard to find objective assessments.

In any case, series mode would be impractical for a whole-house load center connection.

MOVs are practical and better than nothing. If no one else has mentioned it, there are some lightning and other overvoltage events so severe that MOVs won't make a lot of difference. For the critical stuff, you can add a UPS, power conditioner, and/or series mode protection. Oh, and lightning protection.

Otherwise, check your insurance coverage, because if lightning strikes close enough, nothing you do is going to matter.
 
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Old 04-01-11, 06:38 AM
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Wow, we got a good thread going here now!

lawrosa,

The way I see it is you cannot (realistically) protect yourself 100%. While these whole house protectors don't 100% pevent you from losing electronics/appliances, it gives you another layer of protection. The surge strips on your electronics are yet another layer on top of that.

To further what ibpooks was explaining, when a surge comes in the panel protector sends what it can to ground. Now instead of your electronics seeing that 5000v spike, they may see say 1000v. Your surge strips have MOVs in them too. They're going to take that 1000v and reduce it even more.

I work in telecom, so I'm pretty big on grounding/power protection. During a training seminar an instructor put it best. You cannot protect yourself 100%. It's just a matter of how much your willing to spend to do the best you can (afford).

JerseyMatt,

Did you happen to contact APC? I'm a big fan of their backups, always wondering how well they stand behind their connected equipment warranty.

One side note back on the whole house protection..

I've heard from a few sources that a common issue we've seen in our area lately is surges from hot lines falling on the neutral. Maybe blame it on bad power company bonds or what, but I know a few folks that lost a lot of electronics.

I wonder how well a MOV based product is going to help in this case...
 
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Old 04-01-11, 10:13 AM
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Originally Posted by scoob8000 View Post
I work in telecom, so I'm pretty big on grounding/power protection. During a training seminar an instructor put it best. You cannot protect yourself 100%. It's just a matter of how much your willing to spend to do the best you can (afford).
If you want to get some really top-of-the-line surge protection, get some of those protectors they use at cell tower sites. Tons of fancy, expensive electronics connected to a giant metal tower guaranteed to get hit by lightning all the time. They spend a fortune dealing with lightning protection at those facilities.

Did you happen to contact APC? I'm a big fan of their backups, always wondering how well they stand behind their connected equipment warranty.
I know they replaced a bunch of computer stuff for free at a place I used to work. There was some type of transformer fire outside the building which took down an entire server room (some just powered off, some destroyed) amongst many other things in the building (HVAC equipment, lighting ballasts, etc).

I wonder how well a MOV based product is going to help in this case...
Actually if you have good single-point-grounding this type of surge event should be survivable. Where this will wreck you is if your telecom/coax grounds are different than the power ground so you will see multi-hundred or -thousand volt potentials from your phone/coax data pins to neutral/ground.
 
  #29  
Old 04-01-11, 11:22 AM
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MOV are non-linear resistors with negative voltage coefficients. That is, as the voltage goes up, the resistance goes down. Pretty tricky, huh? The other point to know is that all the "surge" must be absorbed as heat within the device(s). This is why a direct lightning hit, or a longer term overvoltage event will not be accomodated. And, the MOV may fail rather dramatically while trying to absorb huge amounts of power!
 
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Old 04-01-11, 01:20 PM
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Originally Posted by scoob8000 View Post
JerseyMatt,

Did you happen to contact APC? I'm a big fan of their backups, always wondering how well they stand behind their connected equipment warranty.
Actually no I didn't have to call APC. I got the computer power supply and router replaced under warranty. The UPS's were already way out of warranty, so I didn't qualify to get them replaced free either so calling them was moot. However, TrippLite did pay to repair my PS3, and I got 3 new strips out of them because they were relatively new and that's how many I sent the warranty cards in for (ALWAYS send in the cards!)
 
  #31  
Old 04-01-11, 02:08 PM
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Question about how to install one of the "external box" units (like the Intermatic PowerGuard IG3240RC)...

My service entrance is a whole house automatic transfer switch (I have a standby genset). There aren't any breakers in the ATS except the main service entrance breaker and the breaker for the genset connection. My main load center is mounted next to the ATS (about 18 inches away). Since the ATS is the service entrance, it is connected directly to the earth ground rod, and the load center is actually a subpanel (floating neutral and ground are separate wires going back to the ATS).

There's no way I can see to connect the surge protection device to the ATS, so will it work just as well if the leads are connected to the neutral/ground/line/line in the load center?

Thanks,
Ira
 
  #32  
Old 04-01-11, 02:56 PM
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Originally Posted by ibroussard View Post
There's no way I can see to connect the surge protection device to the ATS, so will it work just as well if the leads are connected to the neutral/ground/line/line in the load center?
It should work fine connected in the subpanel "main" load center. Connect the pigtail to the ground bus, not the neutral.
 
  #33  
Old 04-01-11, 06:22 PM
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Intermatic still makes whole house protectors however they were not available for MONTHS and are now double the price. Leviton also had some issues as all manufacturers had to meet new UL requirements and that always causes headaches.
I found out today for sure I was wrong, Intermatic still makes a few protectors for residential and light commercial markets. I happened to run into an Intermatic rep today and asked him about it. He told me that Intermatic didn't ship any protectors for several months while undergoing approvals to UL1449 Edition 3. They did, however, drop most of their more sophisticated units, but still market a few systems such as the Panelguard.
 
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