steve1515
Premium
join:2000-08-07
Peabody, MA
 ·Speakeasy
| Whole House Surge Protector?
I've looked at whole house surge protectors and am wondering how they work. All the manuals I've read say that all you need to do is connect them to circuit breakers on each bus (and neutral & ground). I don't see how this could protect anything. Wouldn't the surge go out to every circuit?
Can someone explain how these things work? |
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drjim
Premium,MVM
join:2000-06-13
Torrance, CA
clubs:
| Here's a few to read:
»www.thisoldhouse.com/toh/knowhow···,00.html
»computer.howstuffworks.com/surge···tor6.htm
»www.apc.com/resource/include/tec···ku=PMP1X
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One man's Magic is another man's Engineering. |
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SparkChaser
BURY BECK
Premium
join:2000-06-06
Downingtown, PA
 ·Verizon FIOS
 ·Comcast
| reply to steve1515
The word surge suppressor is sort of a misnomer (IMO). There is another term used TVS (Transient Voltage Supressor) which is closer to reality. See picture
All the ones I know of use MOVs (Metal Oxide Varistor) or SOVs (Silicon Oxide Varistor). Delta has a capacitor they sell, as well.
It basically operates as a voltage sensitive resistor. No current flows through the resistor until it reaches a trigger voltage. At that point current starts flowing and the transient is shunted through the MOV minimizing the affects of the high voltage spike.
Here are 2 suppliers first one uses MOV the other SOV
»www.intermatic.com/?action=div&did=6
»www.deltala.com/how.htm
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My computer has more memory than I do!
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Splitpair
Premium
join:2000-07-29
Cow Towne
 ·T-Mobile US
| reply to steve1515
said by steve1515  :I don't see how this could protect anything. Wouldn't the surge go out to every circuit? Can someone explain how these things work? They work by either shunting the surge across the hots or shorting the surge to ground. The theory of operation is the surge protector takes the brunt of the surge until it either the surge clears or opens a protective device (fuse/breaker) ahead of the surge protector isolating all downstream equipment from the source of the surge.
This is one of the reasons the first line surge protector should be installed at the service entrance. Then if needed secondary protectors can be installed on branch circuits as required. Try to stop the surge ahead of the point where it enters the building and before internal distribution.
Wayne
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If you cannot fix it with a buttset and some beanies you ain't a technician. |
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no_one
| reply to steve1515
It needs a very good earth ground to work properly.
How does one measure how good the earth ground is? |
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SparkChaser
BURY BECK
Premium
join:2000-06-06
Downingtown, PA
·Verizon FIOS
·Comcast
| said by no_one :
It needs a very good earth ground to work properly.
How does one measure how good the earth ground is?
As Wayne said, it shorts across the hot e.g 230VAC or to ground. The ground is provided courtesy of your power company. |
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no_one
| reply to steve1515
Yes and no. The ground is at the service meter I believe usually. Installed by the builder at construction time. The utility may approve it but things happen over the years. is there a way to test it?
The utility does have other grounds on its system but this is the one the whole house would use I think. |
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91439306
15,000 Watts of Bass Power
join:2002-10-16
New Milford, CT
| reply to steve1515
On this topic, I found a decent, inexpensive Intermatic surge protector at Home Depot this week. It's rated for 60KA surge suppression capacity and protects both legs of 240vac. There are two green LEDs, indicating each 120v leg energized, and a red LED for when the unit has been sacrified to a lightning hit. $39 each at HD is cheap insurance for everything in the house.
Even though my computers, music synths, etc, are all powered by a 3kVA UPS, which is running off a Sola CVS installed on that circuit, my sound system is too big for a UPS or a Sola of any manageable size, and our other major appliances are also not on the 'clean' circuit. So the Intermatic unit appears to be a good piece of insurance in this stormy summer.
I am most familiar with the Islatran units we use in broadcast transmission facilities, and from what I can tell, this little Intermatic unit is just about as good. The Islatrans have MOV protectors, inside 3x4x6" plastic boxes, mounted in a 2 cu ft NEMA box and sell for about a grand. The specs are probably similar.
I highly recommend this little gem from Home Depot. CHeap insurance!
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Take care,
Mark & Mary Ann Weiss
My Kurzweil Music at: '»www.dv-clips.com/theater.htm
'»www.basspig.com Bass Pig's Lair
'»www.mwcomms.com
'»www.adventuresinanimemusic.com Stereo Feed! |
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electric6
@sbcglobal.net
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inexpensive Intermatic surge protector at Home Depot this week. It's rated for 60KA surge suppression capacity and protects both legs of 240vac
Use caution in relaying on these little things.
First of all 60kA abs max is a bit low, and surge spec (I^2)t rating is not included. Also the connecting wires are too thin.
MOV elements are not expensive, and using bus rails and wide Cu straps you can construct a high rating inexpensive suppressor.
By the way the best location is the socket under the electric meter. |
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Splitpair
Premium
join:2000-07-29
Cow Towne
·T-Mobile US
| reply to no_one
said by no_one :
It needs a very good earth ground to work properly.
How does one measure how good the earth ground is?
I use a Megger it's an older unit but works just fine.
»www.megger.com/us/story/Index.php?ID=125
Wayne
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If you cannot fix it with a buttset and some beanies you ain't a technician. |
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SparkChaser
BURY BECK
Premium
join:2000-06-06
Downingtown, PA
·Verizon FIOS
·Comcast
| reply to 91439306
said by 91439306 :On this topic, I found a decent, inexpensive Intermatic surge protector I use that one. Wayne (splitpair) has the Intermatic as well but I'm not sure of the model (actually he has 3). My computers are on UPS's and all the other electronic equipment are on protected outlets.
Speaking of musical equipment. When my son lived at home we had a fairly expensive organ that I protected with transzorbs and varistors (before the intermatic was installed) During a storm it got hit and the transzob did it's job saving $1000's
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My computer has more memory than I do!
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91439306
15,000 Watts of Bass Power
join:2002-10-16
New Milford, CT
| reply to electric6
Yes, 60KA is not a huge amount of protection, but for $39, it's way better than no protection.
I took issue with the wire size too, which is why I mounted mine as close as possible to the main ckt breaker and cut the wires to the shortest possible length to make a direct run to the breaker pair and ground bus.
Ideally, the best place to clamp is outside the building, but that's a costly affair. A spark gap is ideal for direct hits, but you also need a lower clamp voltage for the benefit of reducing the spike amplitude that sensitive equipment may endure.
--
Take care,
Mark & Mary Ann Weiss
My Kurzweil Music at: '»www.dv-clips.com/theater.htm
'»www.basspig.com Bass Pig's Lair
'»www.mwcomms.com
'»www.adventuresinanimemusic.com Stereo Feed! |
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Splitpair
Premium
join:2000-07-29
Cow Towne
·T-Mobile US
| said by 91439306 :I took issue with the wire size too, which is why I mounted mine as close as possible to the main ckt breaker and cut the wires to the shortest possible length to make a direct run to the breaker pair and ground bus. You don't want that device on the main breaker. If goes into a hard fault it needs a breaker that sized to the unit per the instructions to trip and not become a fire hazard.
Example the IG1240RC wants either two 15 or 20 amp breakers.
»www.intermatic.com/images/instru···40RC.pdf
Wayne
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If you cannot fix it with a buttset and some beanies you ain't a technician. |
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SparkChaser
BURY BECK
Premium
join:2000-06-06
Downingtown, PA
·Verizon FIOS
·Comcast
| reply to electric6
said by electric6 :
Use caution in relaying on these little things.
First of all 60kA abs max is a bit low, and surge spec (I^2)t rating is not included. Also the connecting wires are too thin.
MOV elements are not expensive, and using bus rails and wide Cu straps you can construct a high rating inexpensive suppressor.
By the way the best location is the socket under the electric meter.
60KA per leg is in the middle to high end of the recommended range for 220V residential service.
The wire size doesn't bother me if it's kept short. It's going through the breaker which is probably going to have more effect on the response than the wire. One could certainly construct their own but I'm not sure how that would sit with the NEC and your insurance company.
The meter box may be an ideal location, however opening it up to add a couple of MOV's would probably be against code and fairly dangerous. I believe MOV's when hooked to the mains require a "protection" device to prevent a shorted or burning MOV hanging on the main feed.
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My computer has more memory than I do!
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Splitpair
Premium
join:2000-07-29
Cow Towne
·T-Mobile US
| said by SparkChaser :The meter box may be an ideal location, however opening it up to add a couple of MOV's would probably be against code and fairly dangerous. I believe MOV's when hooked to the mains require a "protection" device to prevent a shorted or burning MOV hanging on the main feed. Use the correct product and you should have no problem.
»www.efinet.com/index.php?mode=pr···ly_id=36
Wayne
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If you cannot fix it with a buttset and some beanies you ain't a technician. |
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SparkChaser
BURY BECK
Premium
join:2000-06-06
Downingtown, PA | That's a nice solution, Wayne! Definitely the way to do a meter.
Ron |
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91439306
15,000 Watts of Bass Power
join:2002-10-16
New Milford, CT
| reply to Splitpair
Did I say that I connected it to the main breaker? No. I said I placed it as close as possible, so that the wire length would be as short as possible, and that the protection is at the main breaker end of the panel, ahead of the rest of the breakers. The instructions called for a dual 20A breaker for its connection to the panel, which I used.
The EFI surge protector certainly is functionally great, however, I have two issues with it:
1. when it fails, how do you know it's failed (LED? Where?)
2. probably requires an elecrician to install and replace every time it takes a hit and sacrifices itself.
If anyone can answer to the two issues above, then I'd be more apt to look into it.
In forty years at this address, we have never had even one ac powered device fail due to lightning down a power line, however, I am not taking chances with the sheer quantity of costly equipment I have in service in my studio, not to mention the wife's new washing machine, with all its computerized wizardry. We're fortunate to have a good electrical drop (albeit somewhat inadequate to power my stereo to full power, but that's an extreme situation) as far as surge hazards and while neighbors to either side of us regularly lose TVs, well pumps and stereos during storms, for some reason, we have had none of that. Perhaps it's due to the pole pigs on either side of us--we're isolate from both ends of the power line.
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Take care,
Mark & Mary Ann Weiss
My Kurzweil Music at: '»www.dv-clips.com/theater.htm
'»www.basspig.com Bass Pig's Lair
'»www.mwcomms.com
'»www.adventuresinanimemusic.com Stereo Feed! |
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Splitpair
Premium
join:2000-07-29
Cow Towne
·T-Mobile US
| said by 91439306 :1. when it fails, how do you know it's failed (LED? Where?)
What’s the model? On the IG1240RC which is a common consumer model if either green light is out or the red light is on the unit is pooched another is by smell.
I had a 1240 go hard fault after a power company transformer failure. I ended up with two breakers tripped the main and the branch circuit the 1240 is on In addition to that there was a pungent odor of electronics turned to smoke emitting from somewhere around the breaker panel.
After transferring to generator and determining the power companies transformer was off-line (the cutout was laying in my yard again) I left the main (mine) open and reset the branch circuit. Instantly the generator loaded up the breaker tripped and another puff of smoke emitted from the 1240 reminding me not to do that again.
2. probably requires an elecrician to install and replace every time it takes a hit and sacrifices itself. If you wired it you should be able to replace it.
not to mention the wife's new washing machine, with all its computerized wizardry. I have a single 1240 on the utility room circuit due to in part an LG washer in there. Very nice machine low power and water consumption but will all of it’s electronic magic it cannot recover from a simple power failure I ended up putting an APC UPS on it to compensate for our power companies lack of reliability.
BTW Intermatic replaced the toasted unit no charge.
Wayne
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If you cannot fix it with a buttset and some beanies you ain't a technician. |
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jig
join:2001-01-05
Hacienda Heights, CA
| reply to Splitpair
when they say single phase, does that include two phases that are 180 degrees apart?
it just seems strange to offer a product for single phase at 200A. i though that the vast majority of residential service drops are 2 phase 240 (180 degrees apart).
also, question: for you guys that have 2 or three of the 1240s installed... do you install them on the same circuit/breaker as (for example) the washing machine? so you don't actually put in a new breaker, you just piggy back on what's already there?
if you just want to use one to protect the whole house, do you need a whole house breaker? we don't have either a mechanical switch OR a master breaker between the mains and any of the branch breakers. sucks for self wiring. i've wondered if i could have the power company come put in at least a master switch for free.... cause if they won't do it, then i'd just rather replace the whole thing to make room for stuff like the surge protection and a better organized distribution of power.
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A man compounded of law and gospel is able to cheat a whole country with his religion and then destroy them under color of law. -Ben Franklin |
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91439306
15,000 Watts of Bass Power
join:2002-10-16
New Milford, CT
| reply to Splitpair
You misunderstood me. I wasn't talking about the Intermatic. I was referring to the EFI model that installs at the utility meter. I believe that requires an electrician to install. And after a surge happens, say, when you're at work, the smoke would be long gone and I wonder how you would determine whether the unit is still protecting. If you reread my two points, I think you'll be able to answer those questions.
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Take care,
Mark & Mary Ann Weiss
My Kurzweil Music at: '»www.dv-clips.com/theater.htm
'»www.basspig.com Bass Pig's Lair
'»www.mwcomms.com
'»www.adventuresinanimemusic.com Stereo Feed! |
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