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garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
·callwithus
reply to CajunWon

Re: Surge Protection Residential Whole House

Yeah, everything (including that Eaton SP) *SHOULD* be connected to the system via breakers. Would if work if hard wired -- yes, but then you'd have to dump whatever upstream disconnect you have (main breaker or pull the meter) any time you had to work on it (plus, of course, it wouldn't be up to code).

As for distance from the service entrance, sure, assuming the surge is coming from the outside then it's better to keep the impedance from the outside to this device as low as possible. But distance to your house's ground point should be considered, too. Where's your ground rod, you'll want to bond to that.



CajunWon

join:2005-12-30
Cary, NC

2 edits

The outside panel is closer to the service entrance, and the copper ground rod is right there as well. I also have a lightning rod wired (Wire-nut & soldered to prevent corrosion) to that same ground rod.

Perhaps I can build a water tight enclosure for the Eaton Product?
The reason I would consider hard-wiring, without breaker: imo: if the surge comes through as a result of a lightning induced surge from near-by (but not a direct hit to the house) it normally comes in a a series of pulses. If the first pulse is shunted a millisecond prior to the breaker tripping, then subsequent pulses will hit the panel unprotected by this WH/SPD.

The Square D product warranty all say something about being installed by a licensed electrician -which is not going to happen. After reading the Eaton pdf referenced through one of the above links: the 30kA protection will be more than adequate.

Have heard that these devices are sacrificial -after they protect once then they require replacement. Something about a capacitor internally will burn up to absorb (shunt) the spike. True?

btw: what started this was losing a TV just following an intense lightning storm. It was plugged into a Panamax Max6 surge protector and turned off. Even though we had no noticeable electrical anomalies & the UPS devices (connected to the PCs) never activated I feel the situation was circumstantial enough to suspect some sort of temporary over voltage.


Zach1
Premium
join:2006-11-26
NW Minnesota

2 edits

From the sounds of it, I'd bet the surge that took out your TV came in through the Antenna/CATV or Sat connection.

Not discounting the value of whole-house surge protection but many transients enter through the "back door" which many fail to protect. Then there are the jokers who fail to bond these to the building's electrical grounding system. This lack of proper, code-required bonding can cause all sorts of interesting things to happen when lightning strikes nearby.
--
Zach



CajunWon

join:2005-12-30
Cary, NC

2 edits

CATV, after the CATV STB. The old(ish) antenna is my lightning rod & only connected to ground.

The Coax is grounded to the rod, as is the copper water lines & electrical ground wires.


garys_2k
Premium
join:2004-05-07
Farmington, MI
Reviews:
·Callcentric
·callwithus
reply to CajunWon

Enclosing the Eaton device is easy, pick an outdoor rated plastic NEMA box from this page »www.amazon.com/s/ref=nb_sb_noss_···nclosure that will fit the device. One of the smaller ones will likely be less expensive than anything you could make and be rated for that use.

As for connecting it, how will you wire it while the lines are hot? Is there SOME disconnecting means to allow you to safely wire it in?

Regarding the connections, make the wire runs to/from the device as straight (and as reasonably short) as possible. You want the wiring going there to be as low impedance as possible to the high frequency surges, making it shunt as much of the energy as possible from the surge.

Oh, and while you're on Amazon you may want to toss one of these in the basket: »www.amazon.com/TII-Broadband-Cab···3&sr=8-2 to help keep future surges out of that route. I hope you're bonding all of this to the ground rod with tight physical clamps. Solder alone (used to connect a wire to the rod) isn't that good a conductor for high current surges.



nunya
Premium,MVM
join:2000-12-23
O Fallon, MO
kudos:12

These all tie into the panel ground bus.
--
...because I care.


EricNepean

join:2009-11-30
Nepean, ON
reply to CajunWon

In a lightning surge, most of the voltage drop is due to the wire inductance, not resistance, and the current pulse doesn't last very long.

A standard model for a lightning surge is a a current surge that rises from 0 to 10kA in 8us, then drops to 5kA 20 us after start (Ref 2 below); the whole event is over in under 50us. (According to Ref 3 below, this probably under represents a lightning surge somewhat, but at least it provides a reference for some kind of estimate)

A rough calculation shows the the current rise is 1.25kA/us, and for 1/8"dia wire the inductance is about 530nH/ft. The resulting voltage drop is 660V/ft. The inductance doesn't get much smaller unless you use really BIG conductors like water pipes.

So one key thing is to make the leads to your surge arrestors as SHORT as possible (don't worry about size), and in the case of multiple surge arrestors (CATV,AC, phone) to connect them to a common location.

My power entry & panel is at one end of the house, water pipes enter at the other corner; there is a 75 foot "ground" cable between the two, in accordance with Canadian electrical code. bah, humbug. I'd be much better off with ground rods installed near the power panel.

I considered grounding my NAS directly to the water pipes at house entry, and then I realized that in event of a lightning strike, the lightning surge would run from the power entry at the panel via the ground wire to the water pipe entrance. The house AC power lines could rise to 75 ft * 660V/ft = 50kV relative to that water pipe at that point. ZZZZAP Instead I grounded the NAS in the regular way, to the AC wiring ground, this way a similar current surge may travel down the hot, neutral and ground.

references:
1) Inductance calculator (1/8" wire, 400 inches) »www.consultrsr.com/resources/eis/induct5.htm
2) IEC 61000-4-5 section 6.1.1 »www.sanki-e.com/uploadimg/conten···6817.pdf
3) "How to Protect Your House and Its Contents from Lightning"
IEEE Guide for Surge Protection of Equipment Connected to AC Power and Communication Circuits, section 2.3.2


robbin
Premium,MVM
join:2000-09-21
Leander, TX
kudos:1
reply to CajunWon

said by CajunWon:

Perhaps I can build a water tight enclosure for the Eaton Product? The reason I would consider hard-wiring, without breaker: imo: if the surge comes through as a result of a lightning induced surge from near-by (but not a direct hit to the house) it normally comes in a a series of pulses. If the first pulse is shunted a millisecond prior to the breaker tripping, then subsequent pulses will hit the panel unprotected by this WH/SPD.

The Eaton product is has a NEMA 4 rating which is suitable for outdoor mounting. I have a similar (older) model and I like the fact that it is exposed so every time I go by the panel I can verify by the LEDs that the device is still working. As far as the breaker tripping, I don't think that would ever happen. The reason for the breaker is for ease of installation. There is very little, if any, protection being offered by the breaker. I think the ease of replacing a device connected to a breaker is probably worth the small sacrifice in protection. I have similar problems in my neighborhood, in that a lightning strike will travel a fairly long ways over the power lines taking out multiple TVs, computer networks and sometimes even AC control boards at houses fairly distant from the actual strike.

As far as the EATON units, if they take a surge then the LEDs on the device change from green to red and the unit must be replaced.


CajunWon

join:2005-12-30
Cary, NC

1 edit
reply to garys_2k

Agree: seems a bit risky and without benefit to connect HOT, Breakers required:check!

Coaxial protection seemed unnecessary since the shield of a coaxial cable is grounded. The TII products state protecting the center conductor: »www.digicomm.com/tii210.pdf
But this »www.amazon.com/TII-Broadband-Sat···3&sr=1-2 is for use with RG6 and therefore appears the better choice. Perhaps this is just the newer version of the same product. Just ordered!



Raphion

join:2000-10-14
Samsara
Reviews:
·Verizon FiOS
reply to CajunWon

said by CajunWon:

The outside panel is closer to the service entrance, and the copper ground rod is right there as well. I also have a lightning rod wired (Wire-nut & soldered to prevent corrosion) to that same ground rod.

Perhaps I can build a water tight enclosure for the Eaton Product?
The reason I would consider hard-wiring, without breaker: imo: if the surge comes through as a result of a lightning induced surge from near-by (but not a direct hit to the house) it normally comes in a a series of pulses. If the first pulse is shunted a millisecond prior to the breaker tripping, then subsequent pulses will hit the panel unprotected by this WH/SPD.

The Square D product warranty all say something about being installed by a licensed electrician -which is not going to happen. After reading the Eaton pdf referenced through one of the above links: the 30kA protection will be more than adequate.

Have heard that these devices are sacrificial -after they protect once then they require replacement. Something about a capacitor internally will burn up to absorb (shunt) the spike. True?

btw: what started this was losing a TV just following an intense lightning storm. It was plugged into a Panamax Max6 surge protector and turned off. Even though we had no noticeable electrical anomalies & the UPS devices (connected to the PCs) never activated I feel the situation was circumstantial enough to suspect some sort of temporary over voltage.

If you don't have surge protection (MOVs) between the cable TV and your electrical system, I'd bet that the lightning raised your electrical system up as a whole, so nothing connected to it alone was damaged, but that the surge ran through the TV to the CATV line, cooking the TV.

Everything entering the house, EVERYTHING, should have heavy MOVs between all conductors and a single ground point.