damage from blown transformer?

Nate Nagel wrote in news: snipped-for-privacy@news2.newsguy.com:

the surge protector shunts the overvoltage to ground,acting like a temporary -short-,thus it snapped the breaker.That's why many surge strips have an integral breaker or fuse. Depending on the particular surge protector,they should be replaced as they suffer some damage when they absorb surges.The bigger the surge,the greater the damage.They may seem to work,but their surge protection will be diminished or gone.

It could be just a dirt problem and the elements need cleaning. I'd try that first.

It sounds like one branch of the transformer let go,and the second branch fed an unusually high voltage to your house,on one leg of the feed. Thus the failure of the surge protectors;they did their job the best they could.

They have a power oscillator circuit to step up the line V to high voltage,a few 1000 volts,and that circuit may not have much input surge protection. so,it's likely a diode or bridge rectifier shorted,and possibly the power transistor itself.(very likely,IMO)

No experience here,but I would contact the power company first.

Meanwhile,here in central Florida,we have a drought and several nasty forest fires burning up people's homes.

We coulda used that rain!

Is this true even if the "protected" light is still lit? this protector was switched completely off until the power was restored and steady, so I am writing that breaker off as a fluke.

I will; and truth be told I was just thinking this past weekend that it was due for a cleaning, but I think it's schmoked based on the huge flash I got when I tried to re-energize it. I seriously doubt a little dirt on the grids could cause something that dramatic. I'll try it anyway though.

I suspect you're correct; I am also wondering if I should investigate the grounding situation at my house, although I'm not really sure how to assess whether my grounding is sufficient or not. Unfortunately I ordered the TVSS breaker from Dale Electric because I was unable to find a local source, so I will be without protection on that leg until I can source another. Or is there another good option for whole house protection that might be available locally?

As it turns out, I just got back from buying another surge strip and everything in the bedroom is good to go. The Ionic Breeze was apparently switched off, and appears to be functional still, so the only damage there was to the surge strip.

Yeah, I will do that tomorrow once I have a chance to try all the major appliances, I still haven't tried the dishwasher, washing machine, or dryer, although the only failures so far seem to be the air filter and the one surge strip, which based on the date on the back was over 10 years old anyway.

I've got two overflowing cisterns, feel free to send a tank truck by to load up!

nate

OK, well, let me rephrase that. The only failures are the air filter, one surge strip, and the dishwasher, which was installed literally the week before we bought the house. Grr. So there will be no cleaning of the furnace filters today.

I haven't tried the A/C yet either, which is also new.

The washer (ancient) and dryer (new) seem to be OK.

This could be an expensive experience.

nate

Useful is to determine which phase attached to the Siemens TVSS. Then determine which other appliances were on the same phase. Was all other damage also on that same phase?

Makes little difference whether an appliance is on or off for major surges. That little gap in switches will only block smaller surges. If the surge was not finding destructive paths through powered off appliance switch, then, surge typically should have been too small to harm any surge protector. Any protector diverts surges and remains functional. Surge protectors only intended for one surge are grossly undersized.

A TVSS on the breaker box should be 1000 joules minimum. Other manufacturers make protectors that are maybe 2000 joules. A larger protector may withstand surges 8 times larger. And again, must divert surges without damage. Damaged TVSS implies that protector was too small for your location.

Surges can also cause appliance overstress. Should the failed TVSS, tripped circuit breakers, and other failed items be on the same phase, then do some sniffing about on other appliances share that same phase. Seek indication of damage that may result in failure months later.

A properly sized plug-in protector does not fail on one surge. To increase profit margins and to get the naive to recommend that protector, some protectors are grossly undersized. Surge apparently was rather small. Otherwise bathroom GFCIs, clock radios, dimmer switches, smoke detectors, kitchen appliances, TV etc would also appear on that damage list, and other appliances. Many of those appliances were 'on' even when they appear to be off.

A surge struck an Ionic Breeze and protector simultaneously with same potential. Surge was too small to harm the appliance but was large enough to harm the adjacent protector. Age of the protector was irrelevant. That implies a small surge - too small to overwhelm protection already inside the Ionic Breeze.

Finally, also inspect your primary protection system since that is your utilities responsibility and might be sufficient for them to pay for damage:

During a storm may be different than this case. (No storm mentioned)

quoted text -

Homeowners insurance will pay but when working off a $500 deductible with a $150 microwave oven and $100 worth of surge protectors, it was not even considered. That year we had 11 power outages with average of about one day each.

Delmarva Power admitted that they had saved $3 million that year by cutting back in tree trimming. Me and all my neighbors now have backup generators.

My cumulative damages were about $600 so insurance was not worth considering. My brother had a lightening strike on light pole outside his house that took out all his electronic equipment so insurance paid.

de quoted text -

Well, so far my damages are $110 for the power supply in the air filter (found online; still waiting on a quote from the guy that installed it) appx. $200 for the TVSS, and unknown for the dishwasher (previous owners paid $550 for it, installed.) I'm not counting the surge strip as it was fully depreciated years ago.

SWMBO called around to various people today as I was too busy at work to take care of it; they are apparently considering claims for damages. Sounds like I got off light as a coworker that lives a couple streets over (in the direction of the transformer that blew, if my directional hearing isn't completely shot) lost at least a couple of TVs and he has not fully assessed his damages yet. So this may get taken care of; we'll see. The only problem is that according to both the power company and the insurance company, there are a LOT of claims in my area so it may take a few days for someone to assess it. Air filter; well I can live without that for a while especially given that the current weather is such that neither the furnace nor the A/C is running a lot; the diswasher is another issue entirely - I'm a lazy bastard, goshdarnit, and I like to have menial household chores taken care of for me automatically! :)

This experience has got me thinking, though - the furnace itself does have an electronic control board; would it be a prudent investment to install some kind of surge suppression right at the furnace to protect it and the air cleaner should this happen again? The furnace is something close to 20 years old - I forget exactly when it was installed, but I did find the receipt for it in some old paperwork - and I imagine finding a replacement board for that might not be so easy/inexpensive.

nate

This experience has got me thinking, though - the furnace itself does have an electronic control board; would it be a prudent investment to install some kind of surge suppression right at the furnace to protect it and the air cleaner should this happen again? The furnace is something close to 20 years old - I forget exactly when it was installed, but I did find the receipt for it in some old paperwork - and I imagine finding a replacement board for that might not be so easy/inexpensive.

A whole house surge protector would probably be your best bet.

I already have (well, had) the Siemens TVSS breaker in my panel. I'm assuming it was functional prior to this incident. This is why I'm thinking of adding additional point of use protection. I did find a local source for a replacement breaker, but I'll need to get up early to buy it (they keep contractor's hours)

Also, how is a grounding system tested? I obviously have a ground wire running outside or I would have done something about it, but without lots of digging, I can't determine where/how many ground rods I actually have, and even if I did that I don't know how to evaluate whether they're providing a good solid connection to ground. What's the procedure for determining if a grounding system is adequate?

nate

The description from Nate indicates a utility failure that put a relatively long duration (seconds, minutes?) overvoltage on the 120/240 power lines. This is not a "surge", which is very short duration. Both service panel and plug-in suppressors will rapidly be destroyed by long duration events. "Too small for your location" is nonsense.

The service panel suppressor was killed, so w_'s comments on plug-in suppressors are more are nonsense. But w_ has a religious compulsion to attack plug-in suppressors. The description indicates the event was not a "surge".

The plug-in suppressor that was off is probably OK.

Follow up: finally got a response from the power company. To paraphrase: urinate on some woven hemp in a direction opposite that of gravity. Basically they said that their "investigation" determined that a live tree had fallen on some power lines shorting a high voltage line to a lower voltage line and that the tree was outside their right of way so not their problem blah blah blah.

I guess I'm eating this one because my costs are of the same order of magnitude as my homeowner's insurance deductible, and we already made a claim for a water heater that done blowed up last year, so a) there's not much point in it and b) I don't want to end up on anyone's "high risk" list.

I am glad however that I was able to troubleshoot the issues myself and at least narrow it down to board level repairs although I decided not to try to take it down to component level because I did really expect that this was going to get paid for.

I feel bad for my neighbor/coworker now, he said he lost a couple big screens :(

nate