Is this a safe extension lead? - Page 1
Forum section: electronics / general

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 08:23:37 am
content: This is a locally made (Philippines) power strip and I bought it because of it's heavy duty all-metal build.I opened it up to check the 'surge protection' and 'line filtering'.When seeing the copper wire, my immediate concern was the danger if the bottom of the case was ever bent and made contact with the wires.I grabbed a continuity tester and it seems the paint offers protection. There are areas where the paint has been removed, for example the screw holes and a small scratch/scuff.I wonder how much protection that paint really offers and whether you could consider this to be a safe product?

author: M. András
author_rank: Super Contributor
timestamp: June 09, 2015, 08:29:18 am
content: that copper wire should be enameled so its farily safe

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 08:38:24 am
content: The initial turns of copper are enamelled but the ones between the sockets are not.It seems like all the protection is focussed around the breaker switch. Since the wire there is enamelled and they've put a some kind of isolation pad on the case above it.But the further sockets have no isolation pad and the wire is not enamelled.Maybe the risk of the case being bent isn't something that should even be considered? Although they're sold in the general home extension area of hardware shops and suggested for home uses on the manufactures facebook page, they do seem more aimed at heavy/commercial users who would likely mount them permanently.

author: fubar.gr
author_rank: Unknown
timestamp: June 09, 2015, 09:26:21 am
content: I see only two conductors in the photo. No earth wire?I dont think this would pass EU/US regulations.

author: grumpydoc
author_rank: Super Contributor
timestamp: June 09, 2015, 09:33:05 am
content: QuoteIndeed.If the case were earthed, or made from a non-conductive material then it would be fine.Personally I would steer clear.

author: Whales
author_rank: Super Contributor
timestamp: June 09, 2015, 09:38:22 am
content: It's poor that the caps and coils are suspended only by their solder joints -- some dabs of glue would be a good idea, lest they slowly fatigue from dropping and vibration. The power cord looks to be single insulated too

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 09:58:08 am
content: Quote from: fubar.gr on June 09, 2015, 09:26:21 amNo need for an earth wire because pretty much no sockets in the Philippines are earthed! You might get the occasional aircon socket that's earthed but that's about it. When installing your DSL/Phone line, they install a metal post outside your home and earth to that.I just got an email back from the manufacturer saying they are planning to extend the length of the insulation sheet and that their other products already use a full-length sheet.@Whales: Good point about the caps flapping in the wind (as Dave would say).

author: wraper
author_rank: Unknown
timestamp: June 09, 2015, 10:08:46 am
content: Those capacitors are not safety rated (X1/X2), therefore not safe for such use. Very likely to fail too over time as these are very harsh conditions, especially for not specialized capacitors.BTW, I don't see any bleeding resistor. Those capacitors should stay charged when you disconnect it from the mains. If then you touch a pug, you wold receive a zap. EDIT: hmm maybe it is in that black thing where cable is soldered, though it looks like a 3 pin switch. But then why both wires are soldered there.

author: ciccio
author_rank: Frequent Contributor
timestamp: June 09, 2015, 10:24:06 am
content: Quote from: wraper on June 09, 2015, 10:08:46 amMaybe the switch is illuminated, so it needs both live and neutral for the lamp, but switches only live..Best regards

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 10:26:46 am
content: Quote from: ciccio on June 09, 2015, 10:24:06 amCorrect, I should have mentioned it has an illuminated 'breaker switch'. I tried various combinations of turning the switch off, on, plugged in, unplugged and under no conditions could I get the capacitor to hold a voltage, so it's always being bled.Unlike another locally made product I have, a ceiling fan controller. I took it back to the shop for replacement and the sales/electrical guy zapped himself by touching the capacitor.

author: Jeroen3
author_rank: Super Contributor
timestamp: June 09, 2015, 11:10:00 am
content: Metal enclosures should always have earth, or a isolated external power brick. Like with a laptop or a metal smartphone.The earth is there foryoursafety.If 1 of the wires get loose and touches the casing, you cannot safely handle the casing anymore.Or when the metal cuts through the pvc at the cable gland.Return it, and get one made from isolating material.

author: bookaboo
author_rank: Frequent Contributor
timestamp: June 09, 2015, 11:12:33 am
content: Looks safe enough to me.... up to about 12V.Seriously scrap this intermediately, it's horrifically unsafe- No earth- Neutral not switched- Exposed conductors- Poor strain relief- Soldered connections- Cable not insulated properly.

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 11:21:13 am
content: I think you're both right Jeroen3 and bookaboo. Although my intended use is a permanent install for some networking gear, so the chance of physical damage is slim, it's still not ideal.I do understand and agree with the benefit of earthing. It's just that sockets here in the Philippines simply aren't earthed. So if you do buy a product with an earthed pin, it won't actually go anywhere.Trying to return it would be futile, the shop won't have any idea what I'm talking about and will simply plug it into the wall and say "but it's working".I'll just buy plastic cased ones in future. I just wanted to support the local brand; All of their equipment uses metal enclosures.

author: Jeroen3
author_rank: Super Contributor
timestamp: June 09, 2015, 11:32:29 am
content: Do you have RCD's installed? You should have. It's your safety, and the safety of all other residents, including possible childen.- It's common to not switch both conductors in cheap consumer grade plugboxes.- It's also common that instead of wire, long metal (not always copper) strips are used. Which is not inherently unsafe if kept inside the box.

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 12:09:30 pm
content: Quote from: Jeroen3 on June 09, 2015, 11:32:29 amI don't, and I'm renting so it's not practical for me to swap out all the breakers. GFCI/RCD equipment is a little difficult to find locally.I'll have to research 2-wire GFCI/RCD extensions / socket replacements.

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 12:26:39 pm
content: A little off-topic to my original question, but for anyone interested in how homes are wired in the Philippines, you might want to checkhttp://myphilippinelife.com/philippine-electrical-wiring/Although this guy is trying to do things 'the right way' which is probably a bit better than most.Edit: Oops, I just realised that I'm a new member and then linking to an external site. Just to clarify, it's not my site and I have nothing to do with it. I just came across it while I research what I can do to improve the electrical safety in the place I'm renting.

author: Jeroen3
author_rank: Super Contributor
timestamp: June 09, 2015, 04:34:18 pm
content: Nice website. Shows how much difference there is between acceptable standards in the world. Assuming you read it from somewhere else of course.@stinkysteve, you can get plug-in RCD units, I recommend you get one for your electronics desk. If you have one

author: m100
author_rank: Regular Contributor
timestamp: June 09, 2015, 04:47:07 pm
content: Quote from: bookaboo on June 09, 2015, 11:12:33 amNeutral not switched isn't by itself unsafe*, of course with a reversible plug it can be.* Single pole live switching is used on a great many UK multiway adapters from reputable manufacturers and sources. I would have no concerns about me or anyone else using them. Of course the UK uses a three pin polarised and fused plug.

author: stinkysteve
author_rank: Contributor
timestamp: June 09, 2015, 05:02:22 pm
content: Electrical safety isn't exactly huge in the Philippines. Most electricians I've had in my home refuse to turn off breakers when replacing light fixtures or wall sockets. You have to do it before they arrive to avoid an argument over it.Most sockets are just two pin and even if they have the hole for the ground pin, it usually isn't connected to anything. Most appliances have identical pins so you never know which lead will get neutral and which will get hot; it depends which way you plug it in.I have been shocked more times that I care to admit. Sometimes when plugging something into the wall or removing it and accidentally touching the pins. Or more often it's on light sockets that have exposed metal. I guess I've been lucky that they're just shocks, although I can remember at least one that was like being hit by a truck.Finding RCD / GFCI stuff here is a little difficult. I did finally find a company selling replacement sockets for the wall but those plug-in type RCD units would be better for me. I think I'll keep hunting and then just use them all around the house.For anyone curious, here's some quotes from an email conversation with the manufacturer. Before I'd have said I'm a fan of this local manufacturer but now I must admit I have my concerns.QuoteQuoteQuote

author: Ian.M
author_rank: Super Contributor
timestamp: June 09, 2015, 05:30:31 pm
content: It has the potential to be rebuilt to be safe and effective assuming YOUR location has properly earthed polarised sockets. It would need rewiring with a three wire double insulated lead fitted with a polarised plug with earth, a fuseholder or circuit breaker, a earthing stud in the box to terminate all earth connections to, an earth bonding cable between the box and the cover and a much longer vulcanised card insulator. It would also need the caps replaced with appropriately rated ones. Also note the melting round the lower switch terminal from when it was soldered. If that switch is fit for purpose and is an effective overload cutout, I'm a monkey's uncle!Is it worth doing that? probably not. If you need a rugged extension lead get one with a rubberised socket not a locally produced P.O.S. metal box one.

author: stinkysteve
author_rank: Contributor
timestamp: June 10, 2015, 06:12:58 am
content: Thanks Ian, I think your post pretty much sums it upI'm planning to test what the switch actually does in the case of a short circuit. I'm guessing it's not going to be pretty.I tested another of their products to see what would happen in the case of a short circuit, there was a big bang but the circuit breaker switch didn't "trip".

author: helius
author_rank: Super Contributor
timestamp: June 11, 2015, 04:54:24 am
content: It's useful to learn how people deal with (or in this case, avoid) safety issues in other contexts. In some places, simply keeping the power on is such a problem that electrical safety gets ignored.The mixed-type US/CEE7 socket is also interesting, since appliances with those plugs run on different voltages. It reminds me of the old NEMA 2-15 outlets you sometimes see in old buildings.

author: Towger
author_rank: Super Contributor
timestamp: June 11, 2015, 08:27:30 am
content: The Philippines uses US plugs and sockets at 220V and 60Hz. The mixed socket is not what you would normally see on a wall in a house. The NEMA plugs dates back to American rule, I believe there were some areas with legacy US 110v systems.About 10 years ago my father in law (mechanical engineer) and brother in law (electrical engineer) were looking at the possibility of setting up a business to upgrade domestic houses with RCDs etc. The brother in law worked for ABB at the time, so no problems in sourcing quality equipment. However, they found that people could not see the point in spending any money on upgrading something which worked fine...

author: stinkysteve
author_rank: Contributor
timestamp: June 11, 2015, 03:00:58 pm
content: I bought a replacement extension cord today. It's a "made in china" but one of the biggest local competitors to the extension lead I originally posted.Generally it seems much better. A plastic case, crimped wires, double insulated main cord and a ground. Although my sockets don't support a ground pin.