ECN Forum Forums Photo Discussion Forums Violation Photo Forum "Outlet Strips" Am I wrong here?

Boy... you're tough to convince SolarPowered.


Every time I have found a strip in this condition, it could be directly attributed to user abuse. These strips are intended to be used with low wattage/amperage equipment. For example, I have never come across a damaged unit that was used for computer or other similar office equipment.

But, when you plug (and this is a real life example) a microwave, refrigerator, toaster oven/or toaster, coffee pot, and a portable heater, all into the same strip... bad things happen pretty quick.

Heck in the scenario I laid out, the portable heater alone (usually rated at 1500 or 1800W) either takes the strip to its intended load or way beyond (80% of 15 amps = roughly 1440W). See, NEC 210.21(B)(2)

So, even though the strip may be designed for 15 amps, when you load it with 30 amps... and you have the bimetal heating effect occuring... fire happens, circuit breaker doesn't trip... people choke on smoke.

Convinced??? Anyone else want to help me argue this point?

But what if the breaker was rated at 15 amps and the wire was 16AWG rated at 13 amps? And most of the so-called, "surge protectors" are just circuit breakers, no surge protection!

I think usually to handle the "surge protection" three MOV's (metal oxide varactor) are soldered across the cord leads. They look like a disc capacitor. And do little more.

That's exactly what it is, Physis.

In addition, some up-market models have a little circuit for noise supporession, consisting of a few capacitors and a toroid.

The cheapest of the cheap are just a box with six outlets molded into the plastic case. They may have a circuit breaker but there is no surge protection or noise suppression.

I actully like the coil and capacitor job. It makes a second order (12 db per octave) filter. The smaller the coil the higher the frequencies it operates on though. The little coil ones can miss a lot of slower noise that has more energy.

Hey Joe... any reason you took out my picture of the fried RPT from this thread?

Just curious. It's a good example and it's worthwhile for people to see what can happen to a strip that is not used according to its listing and labeling.

If it's a space issue, maybe we should put the picture into a thread of its own. Let me know if there is another problem.

Glenn

Glenn:

The link to the image was on my FTP site and with recent changes was lost, so "Yes" please resend it to the webmaster here and start a new message to reaffirm the issues.

Speaking of that image, I'd suspect that that damage could, or maybe even did, occur using it within the maufacturers instructions.

Update:

Pictures have been reposted above.

I'm from Ireland and spent a little time in the USA over the last few months and would have to agree that there is some rather scary misuse of powerstrips going on over there.

e.g. I saw a 15A powerstrip plugged into a 2-pin zipcord extension cord using a "grounding adaptor"... this was supplying power to a small window mounted A/C unit & computer equipment! ... out of curiosity I touched the zipcord and it was actually hot!

Anyway, the situation in the UK and Ireland is simlar in many ways, people have the same need to plug in large number of small appliences (computer equipment, mobile phone chargers, desk lamps, audio/video equipment etc) and we also use powerstrips to do this... however, there are a few differences... Powerstrips are always wired with cable that can carry at least 16Amps with a comfortable margin of safety. All of our plugs contain an individual fuse rated 3 to 13Amps. If you overload the strip, the fuse in the plug blows.

Also, because all plugs are fused, it's very difficult to overload a wall outlet as you would have to bypass the plug fuse.

Also, there is no such thing as a non-grounded plug, so all extension cords and other devices are fully grounded.

I've also seen office systems here that have fused outlets to prevent employees from plugging heaters, coffee makers and other heavy appliences into circuits that are intended for use with IT equipment. The outlets under their desks could be fused at 5amps.

(I know this kind of fusing arrangement would be more difficult in the USA as you guys don't have any sort of commonly available standard cartridge fuse. In the UK and Ireland because every applience has a fused plug, these small fuses are available easy and cheaply in any hardware store / corner shop.)

The tiny resetable breakers used on US powerstrips seem really cheap and nasty, I'd much rather see a simple fuse used.

Also, in an office system, why not use IEC connectors under the desks for computer equipment? IEC powerstrips are quite common place in Europe for server and studio equipment to avoid the risk of people connecting non-IT equipment to these circuits.



Non-standard UK plugs and socket outlets are also available for these kind of situations e.g. for use on UPS or filtered circuits.

[This message has been edited by djk (edited 02-26-2005).]