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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
122836	2003-02-21 02:29:00	Hi. Last night I was replacing a lightbulb, turned on the lights and the new lightbulb didn't go. I thought this was weird so I tried the new bulb in another socket and it went ok. My next theory was that i didn't screw it in tight enough, but that wasn't the problem either. My next theory was that the contacts had been pushed back and weren't touching the lighbulb, By this stage I had been up and down the ladder turning the lights on and off, so I decided to leave the lights on. I stuck my hand in the lightbulb to move the contacts........ yep and i got 230 odd v jumping down my arm. The question is, Since the lightbulb won't light up but will give me a shock, does it mean that the light cradle has power running through it but isn't earthed? With me sticking my finger in there and me been earthed would have resulted in the cradle coming to life and giving me a jolt?	roofus (483)
122837	2003-02-21 03:35:00	There's a combination of things here. The modern lamp sockets are cheaply made. They are mostly rated for 60W bulbs. To get reasonable light, most people put in 100W, 150W or 200W bulbs in. 90% of the watts come out of the bulb as heat, not light. Hot air goes up. The scoket is above the bulb and gets hot. The springs on the contacts weaken. The plastic around the sockets distorts. Our bayonet (push and turn) sockets have a fixed amount of movement. The thin brass pieces which define the movement of the pins in the side of the bulb base can come away from the plastic moulding, and if there's only one there (cheap means 2 small pieces of brass, not one continuous piece all around the holder) the bulb will be cocked over and touch only one of the two contacts, therefore no work. Replace the socket. Preferably with a traditional brass/ceramic socket. The shock you got: if the switch was still on (watch out for 2-way sowitches ... you can't say "up is off"), you just got a shock, by poking your finger into a live electric socket. Duh. :D If the switch was off, the wiring is wrong. It happens. It shouldn't. Get it fixed. But people shouldn't poke their fingers into electric sockets.	Graham L (2)
122838	2003-02-21 04:27:00	An even simpler suggestion is that the Neutral connection is faulty (probably in the connection to the socket) The Phase is connected as you found out, but the lamp will not go if the Neutral return has no connection . Probably the wire is cooked, along with the terminal due to heat from the lamp as Graham L suggests . It does not matter with a bayonet socket which wire goes to which but it DOES matter if its an ES connector (Edison Screw) Otherwise you will liven the accessible metal . Ouch .	godfather (25)
122839	2003-02-21 04:32:00	But it matters if the neutral is switched, not the phase. (I forgot cooked wire, but that is usually cooked insulation. A couple of twists and the fuse blows. )	Graham L (2)
122840	2003-02-21 05:22:00	I can't work out if your name is Doofus. Geez, your must be brighter than a 250watt globe to stick your finger is the socket. What an idiot	dot_com (558)
122841	2003-02-21 05:58:00	dot com: Roofus & I have had our differences, but we are friendly now. He is very technically competitent, but this must have just been a momentary slip. It happens. I can recall circumstances where even experienced electrictians have come to grief. As GF says, he may have been lucky that the neutral was disconnected. Lets be thankful that he survived.	Bazza (407)
122842	2003-02-21 06:13:00	> dot com: Roofus & I have had our differences, but we > are friendly now . Whats that got to do with anything > He is very technically competitent, Yes he sounds it . Sticking his finger in, is a dumb as it gets > even experienced electrictians have come to grief . > Yes, they all stick their fingers in the socket	dot_com (558)
122843	2003-02-21 07:12:00	Bazza and Dot_com Keep it up fellas... I love it. My wife sometimes wonders why I end up laughing so much after my daily fix. More........!!!!!!	Scouse (83)
122844	2003-02-21 09:05:00	Roofus, Were you wearing your gumboots at the time?	dot_com (558)
122845	2003-02-21 09:23:00	> But it matters if the neutral is switched, not the > phase. (I forgot cooked wire, but that is usually > cooked insulation. A couple of twists and the fuse > blows. ) In 30+ ++ years I have not found a switched Neutral, but I am sure they may exist. Its just the thought of an accountant changing a lightbulb and using a digital (as in a finger) multimeter that cracks me up... :)	godfather (25)
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