Surge Protection Device Questions

[JHZR2]

Hi,

Looking into surge protection for a few new items in the home. Does everyone really use these?

In the last 30+ years, my parents lost a microwave and a dustbuster when a tree fell on a line, and then a PCMCIA modem once from an actual lightning strike. That's not a lot of damage, maybe $200 on 30+ years. Ive never lost a thing.

That said, safe is better than sorry, and breakout into multiple outlets is a good thing. However, I dont know that I trust the way these things are defined. For example, Belkin will claim some level of protection, but then it is split 1/3, 1/3, and 1/3 by H-N, H-G and N-G respectively. So for a "918J" device, it protects against 306J on each combination.

Is this somewhat misleading, or is this standard in terms of what is offered? If Tripp-lite states that their device is 540J but does not break it out past that, should I assume it is 1/3, 1/3, 1/3 like the Belkin, or might this unit be 540J per line combo and more straightforward in their advertising?

Also, what is the deal with "filtering"? different units seem to show 40-43dB at 150kHz - 100MHz. Those are some serious harmonics on 60Hz distribution. I assume it is injection of RF into the lines? Does this have much of an effect on anything really and dould the devices have enough capacitance or whatnot to adequately filter?

Thanks!

 

[Quest]

Surge protection is, IMHO mandatory these days for the 2 major occurences in the line (power line/AC source, etc.): (1) natural disasters such as thunderstorms, lightening, tree falls knocking down power lines, etc.; and (b) man-made/induced spikes, such as AC induction motors, fridge kicks in,etc.

2 things worth considering when pursuing surge protector: (a )get highly reputable ones from brand-name suppliers such as Tripplite, APC, etc. and (b) get as close (or lower) to the AC line voltage rating as possible (in my case: I buy the ones that are 330V AC to let them work as soon as a spike is detected.

The main component in surge protection called MOV (metallic Oxide Varistor) and quality differs from 1 component manufacturer to another. Don't expect a 3 dollar chinese made power bar with surge protection to protect your stuff sufficiently.

I personally go with Panasonic or Siemens MOV all these years, citing very consistent reliability and predictable failure mode. I've seen cheep no-name (unidentified, typical of over 80% of cheep chinese made electronic components these days, from computer PSU to LCD tv, etc.)ones would pop or smoke or not clamp at all.

AC's EMI/RFI filtering is a totally different subject. Used to be (up and, until the late 60s or early 70s), this subject wasn't well-explored and typically under-estimated by a lot of consumer-level electronics.

In those days, the primary source of AC line noise were AC induction motors, or similar (fridge kicked in, etc.) and of lower harmonic registers to begin with, so that they can be safely disregarded.

Now, with lots of switching power supplies (major AC line noise, see the FCC label on those properly certified ones) in use, a lot of sensitive electronic components that are not tolerable to AC line noise, etc., having a high frequency AC line filtering is beneficial (while some may claim otherwise).

These HF line-borne noise is rather broadband and most cheep electronics cannot tolerate it w/o proper filtering in place (and start misbehaving).

For medical/professional filtering, I use corcomm, TDK etc. Delta is ok but not my cup of tea.


Q.

 

[JHZR2]

What about the ratings? Seems to me that they are all a bunch of advertising (regarding Joules, not stuff like UL 1449).

Ive mainly used tripp lite though I believe I have an APC somewhere in the house. Belkin does not seem to be as well specced... Is Belkin an OK company to purchase from?

 

[Loobed]

You have to be careful about the UL listing for the surge suppressors. Some surge suppressors have a UL listing but the UL # is for an extension cord and not a surge suppressor. UL charges more for surge suppressor listings than they do for extension cords.

I had a printer go out when someone ran into a power/telephone pole. The printer was connected to an APC surge suppressor.

 

[JHZR2]

Also, do these devices protect if not given a proper third (ground) conductor?

 

[EricF]

for the best possible protection..a UPS is the only way to go.
APC used to be good..to me they're all marketing hype now and they throw fancy voltage ratings out to confuse people.
for surge strips, you want to look mainly at the Joule rating.
the higher the joule rating, the faster the surge clamping action. APC is usually rated pretty darn low. radio shack's are pretty high, over 2000 usually. I have several APC's and they're cool looking but they don't run the sensitive stuff.. my DVR's computer router, dsl, etc.. are all on battery backup units. Some APC, others belkin, I'm not looking for keeping things running when the power is out, moreso the protection of the devices.

 

[odie]

Tripp Lite make very good surge protectors with noise filtration . We have the ISOTEL 4 and 6 oulet ( http://www.tripplite.com/en/products/model.cfm?txtSeriesID=825&txtModelID=106 ) for many years to protect stereo gear , tv , etc.. Here's their products , http://www.tripplite.com/en/products/product-series.cfm?txtSeriesID=825 . These can found at STAPLES and OFFICE MAX .

 

[JHZR2]

yeah, isobar is what I have mostly throughout the house.

I mainly popped upon this question because we put some new small electronics in the house and the manual actually stated to provide surge protection... So I was looking for small protection devices to use.

A few weeks before our refrigerator was acting flaky, and it turned out to be a bad mainboard... The refrigerator was plugged directly to the wall...

 

[benjamming]

Quest mentioned the cheap Chinese stuff & the, what I assume, not cheap Chinese stuff, i.e. Tripplite, Siemens, Panasonic, etc. bearing in mind that there is stuff made in China & then there is stuff made (well) in China. However, are there any made domestically?

 

[PandaBear]

Originally Posted By: benjamming
Quest mentioned the cheap Chinese stuff & the, what I assume, not cheap Chinese stuff, i.e. Tripplite, Siemens, Panasonic, etc. bearing in mind that there is stuff made in China & then there is stuff made (well) in China. However, are there any made domestically?


I think when "Cheap Chinese stuff" is mentioned it is assumed that it is "Cheap Chinese branded or no name branded stuff".

 

[ARCOgraphite]

Can't you buy some components and build your MOV and filters into the wall box? I still unplug my RG6U from the wall when a storm comes. I lost a LAN card and a modem the previous storm - modem was rented comcrass and replaced FOC, the lan card was 12 bucks - still cheaper than the price of 1 good surge strip.

 

[kb01]

Maybe I've just been exceedingly lucky but I've lived my entire life in old houses and apartments, with predominately ungrounded branch circuits. Using the 3-to-2 prong adapters, as well as ungrounded GFCIs has been a way of life for a very long time and surge protectors provide no protection without a ground wire.

In all those years, I've had yet to experience a noticeably decreased lifespan in any of my electronics.

 

[Quest]

Cheep chinese stuff are the ones that sold under non highly recognised ones (other than tripplite, APC, Belkin, Eaton, etc.). Those are the ones that we should avoid at all cost.

The way I see it: ideally, I would like to have at least 2 (preferably all 3) safety measures built in:

(1) a 15 amp small breaker built-in, similar to those with a black button that "pops" out when the circuit is overloaded, needs to push it in to reset, etc.

(2) MOV of proper ratings and high quality (not some cheepo or counterfeited ones that doesn't even past proper UL/CSA tests).

(3) GFIC or not is, for the most part, not too importand.

@kb01:

You do not need ground in order for GFICs to work properly. Case to the point: I've re-rigged (by code) some 50s houses with only 2 prong AC outlets (w/o the 3rd/ground wire to begin with) with GFICs.

The full-protection arrangement RE: surge protection of: L-G, N-G, L-N is, IMHO the best. This will protect any possible line-borne spikes/surges that came along from Live or Neutral. In the case where your ground wire is in-question, L-G and N-G will protect your equipment.

Lastly: I've been restoring/repairing APCs, Tripplites and even Eaton UPS for the past decade: nothing betters than these brand name units as far as reliability's concerned. I'd stay away from PwrCentury, Belkins and many other non-recognised brands from far East: they will die in the most unexpected ways unimaginable.

I also don't buy into the idea of UPS'ing all the home appliances for the sake of line sag/surge (AVR) or spikes/surge protection, or even brown/blackouts (only on my computer/networks), citing the lack of need of AVR or power backup (square-waved 120VAC?not in my audio systems, thank you).

Q.

 

[JHZR2]

Good info and good to know that it works on two-line systems, as I still have a few circuits like that in my home.

What's your take on the ratings schemes for Joules? If Belkin says they provide 918J, but it is 306 per line couple... and Tripp lite just says 515J, is it best to assume that Tripp lite is 1/3 of the 515 per line couple, or that they are 515 each?

Seems like a good way to misrepresent your product if you are Belkin and make claims like summing up individual protection versus giving a single value that is consistent.

 

[Quest]

@JHZR2,

Unless you can take apart the surge protector units and look at the labelling on the MOV body itself (and then cross-reference to the manufacturer to find out the exact Joules rating @ that given let-through voltage, otherwise, it's as good as just being an arbitrary figure.

A good MOV should be able to let through the "spike" voltage (typically happens in the matter of nanoseconds, and can peak by over 1kV or more) gracefully and transform some of them into heat. Over time, a good MOV should deteriorate gracefully until it shorts itself out. When properly designed (combined with a fuse or a 15 amp trigger breaker beforehand), a finite life MOV should die off and short itself out and with burn out the fuse (thus those little LED lights should go off, or trigger those built-in power bar breaker.

I typically go with somewhere around 500Joules @ 330V rating for typical 1 single electronic units, and would seldom goes beyond 1000joules@ 330V.

Also: never fall for multiple paralleled MOVs design for they will fail in the least expected manner due to inconsistencies in matching (each MOV have slightly different parameters, and just like lytic caps: variations can be as much as 20%, so paralleling them to get more joules out of them is as dumb as it gets).

Plse take care.

Q.

 

[odie]

Here's another company that produces surge protectors . PSP , http://www.pspproducts.com/index.php . Here's some products that may be of interest . http://www.hometownutility.com/custserv/energy_info/brochures/light_season.pdf . I have their surge protector for home entertainment , here's that unit , http://www.pspproducts.com/admin/pdf_files/1232568342Plug_In_Warranty_rev011509.pdf . Has worked fine so far . Here are some other products . http://www.pspproducts.com/html/indexed_products.php?category_id=6&midcat_id=2&subcat_id=19 .

 

[Papa Bear]

Originally Posted By: JHZR2
Ive never lost a thing.


That pretty well says it all .......
An expensive suppressor "may" save a piece of equipment under certain minor glitches but it won't save it from a lightning bolt that has just traveled 3/4 mile through the air and is headed for your house.
That's what insurance is for..... take your suppressor cost and lower your deductible instead.

 

[Quest]

Last but not least: if your area is plagued with thunderstorms or lightning that will kill electronic stuff, trust the good ole faithful instead: (gas discharge tube) (known to HAM folks since the dawn of ham, although most of us, incl. yours-truely, used the cheep trick of a sawtooth patterned metal strips with air-gaps on a hard wood board just for cheep's sake, I'd go with gas discharge tubes to handle any seriously large, high energy spikes that came along with lightning strikes. They begin to work around 500v and can take as much energy as it can handle, w/o missing a beat. Response time may be a tad slower than MOV (into approx. 100 to 200nanoseconds, if memory serves). but coupled with MOVs, breakers, etc. it would save a lot of frustration over the cost of burned electrical devices.

But then again: I'd rather physically unplug my devices (or have them on power bar with breakers + on/off switches and just simply power them off when lightning storms around.

Q.

 

[JHZR2]

Another question... Loads that have (relatively) high inrush currents which will effect power quality - refrigerator, dehumidifiers, etc. These are the loads that make it necessary to have filters on other equipment's surge protection devices.

But what if you put the "noisy" loads on a protector system with filters on it. Would they serve as very small "soft starters", and help reduce the line noise themselves? Is it therefore more important to put filtration on the big peaky loads than the smaller ones?

 

[Quest]

AC induction motors, etc. will create high inrush current, aka "spikes" or "surges" that are very small 10s if not 100s of a sec) but not broad frequency, meaning that it doesn't come with a lot of high frequency line noise.

With that in mind: in-rush current should be best dealt with MOVs, lines that are very "noisy" with lots of high frequency RF noise should be dealt with AC line filters.

Case to the point: have you ever hear an AC line (overhead AC pole)hums with radio station broadcasts when situated close to a high power radio broadcast tower? Those are one of the scenarios where your AC line will come with radio station broadcasts (RF noise) and RF is what AC line filter is meant for.

Hope that helps.

Q.

p.s. there are lots of power supplies that generate RF noise back into the AC line: your cell phone charger, computer PSU, TV power supply, etc. Anything that uses switch mode (aka "Switching") power supply design will introduce a small amount of RF noise back into the AC line, thus polluting it.