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| Thread ID: 30495 | 2003-02-21 02:29:00 | OT: A ? on electricity | roofus (483) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 122846 | 2003-02-21 09:26:00 | Sticking yer finger in the socket seems like a good way to find out if its live or not, especially if yer hard as nails. Cheaper than getting a sparky. | Danger (287) | ||
| 122847 | 2003-02-21 11:54:00 | Good one Roofus!! Really kiwi blokie thing to do. Not like those pansy sparkies who need to use a test meter. | Peter M (852) | ||
| 122848 | 2003-02-21 20:44:00 | Yes I was a retard to stick my finger in there, i'm well aware of the dangers and it was a lax in judgement. Anyway once bitten twice shy. THe bayonet is rated at 100w and its using a 100w lightbulb. Nothing is melted or distored. So my theory is that the neutral/ground is not connected. or the connections have come loose. |
roofus (483) | ||
| 122849 | 2003-02-22 00:04:00 | Hmmmm . . . . . . There are two separate issues here . The light not going, and the shock . Dealing with the important one first, to get a shock at all, there had to be a live power supply point for you to touch and a path to ground from your body (via earth wire, neutral wire or other grounded object) . Normal domestic light fittings do not have an earth connection unless they are made of metal, in which case the whole of the socket is usually made of metal as well, and the rest of the light fitting is also earthed . So, in a non-earthed light fitting the shock would either be (a) across your finger tip from contact to contact in a bayonet socket or from centre contact to outer screw contact for an edison-screw socket; or (b) from your finger down your arm and through your body to the main point of contact with ground . You will not get a shock in example (a) if the neutral is open, but you will in example (b) . In an earthed light fitting with an all metal bayonet socket the shock would either (c) be across your fingertip and simultaneously through your finger to the earthed outer body if the neutral was intact, or just across your finger to earth if the neutral was open; (d) again from your finger down your arm and through your body to the main point of contact with ground if you somehow managed to just touch the live contact and avoid any other part or contact in the fitting; or (e) from hand to hand if your other hand was touching the earthed metal of the fitting, in which case you would be a very lucky person to be able to tell this tale . Note: I did not mention screw type sockets for the earthed fitting example as I have never seen an all metal edison-screw socket, they do not exist except for low voltage lamps due to the horrendous risk they would present . Reasons for the light not working are much simpler and have been well covered already, but I make the point that a light that worked until the bulb blew, coupled with a new bulb that works in another socket quite simple means that one of three situations exists . 1) A non-standard bulb with slightly different physical construction - there are plenty of these around on non-name cheapies . 2) The socket is damaged, though I couldn't follow the"two brass strips" argument as I sense this is an edison-screw fitting and cheapies usually only have one strip . Even if there are two and one is not making contact, the other is enought because the second connection is via the middle contact on the base of the bulb . 3) The neutral wire to the socket is broken/burned out . I will have one of my rare disagreements with Godfather here and say that switched neutrals are more common than ever now . They usually come about through home renovators, painters & decorators or other persons removing and reconnecting wiring on the basis that you shuffle the wires until it works, and if the light goes when you have finished it must be right . I NEVER assume a neutral or earth is dead anymore, I have found too many live examples . Moral of the story is: always switch off before working on anything electrical and use the electrician's prove-test-prove principle if using an electrical tester to check for voltage . (Prove that the tester works, test the circuit for power, prove again that the tester still works) P-T-P is a "very good idea" as more than a few dead electrical workers would agree, if only they could come back and do it properly next time! Cheers Billy 8-{) :| |
Billy T (70) | ||
| 122850 | 2003-02-22 02:32:00 | Billy: you don't need to be connected to a neutral or earth to get a good belt from 230V. You can feel it. And you don't need much current to be killed. Falling off a ladder can do the trick; the shock just makes you fall off the ladder. :D A retired electrician I knew once always tested for 230V by grabbing the connector. (Don't try this at home, kids). He lived to retire. |
Graham L (2) | ||
| 122851 | 2003-02-22 03:14:00 | Too true Graham, leakage current or even capacitive current will give a tingle that might cause the unwary to fall off a ladder, but I was really talking about shocks that have the potential (pardon the pun) to injure directly . I have a friend who lost a sizable proportion of the flesh at the base of his thumb by accidentally contacting the terminals at the back of an on/off switch . The shock was not life threatening but the burn was deep . As for electricians who intentionally liven themselves up, they live longer than they deserve to, but isn't it said that the good Lord looks after fools and children? I added to this post because I believe that information on electrical safety should be promulgated widely, and there is no more important place to do this than a public forum populated by people who might just be working on their own electrical installation or equipment from time to time . Cheers Billy 8-{) :) |
Billy T (70) | ||
| 122852 | 2003-02-22 11:46:00 | The other day, I was looking for a electric plug, so unscrewed the one off the end of an extension cord. It wasn't till later that I discovered that the other end of the chord was still pugged in and switched on. Its a wonder I didn't get a blast like Roofus. BALDY:-) |
Baldy (26) | ||
| 122853 | 2003-02-22 16:24:00 | > The other day, I was looking for a electric plug, so > unscrewed the one off the end of an extension cord. > It wasn't till later that I discovered that the other > end of the chord was still pugged in and switched on. > Its a wonder I didn't get a blast like Roofus. > > BALDY:-) And would we have had to call you CURLY from then on? ;-) |
Pollly (1416) | ||
| 122854 | 2003-02-23 01:03:00 | You wanted a plug, Baldy, and the other end was still plugged in? You use those double ended extension cords (a tapon at each end) do you? :D (This is a bit of a technician's joke. Don't do this, folks). |
Graham L (2) | ||
| 122855 | 2003-02-23 01:40:00 | Hey I resent that cheap crack about accountants GF ;) Keep them for the lawyers | wotz (335) | ||
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