Watch Your Feet !

[brianbrain]

I have to. Every bloomin' day! My screw-in bulbs are forever going off and I have to get the step-ladder out and give them a tweak - usually unscrew a little and then screw back up. And sometimes the thin metal thread inside comes away with the bulb, so I have to take the whole thing out of the ceiling and fiddle with it to get the metal thread back inside.

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And I thought that only happened to me! Great to hear someone else has the same problem I had considered buying some "energy saving" bulbs until I witnessed two of them self-destruct, scattering fragments of glass across the room.

It would be easy enough to wire up a florescent strip light from the lighting circuit. Perhaps that's the best solution. They are cheap, reliable, and easy to service/replace.

[cobra]

its especially dangerous as they use 240 volts which is lethal, as opposed to 110 volts that some countrys use which wouldent hurt you much

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Ummm...It's not the voltage that is dangerous, it's the amperage.

Ski....

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... and amperage is a function of resistance, always wear some decent shoes when doing any electrical, and always use just one hand to negate a contact going across your chest as opposed to going down one side.

Though service drops and other elect look terrible, you never really hear of many electrocutions, even during rainy season ..

[andy50]

thats good advice cobra

regarding the 12 volt battery issue,yes there are hundereds of amps available "on tap"from a car/truck /tank--battery but as it is only 12 volts there isnt enough volts to allow the amps to flow through you ,just go out to your car,lift the hood and grab each terminal of the battery --no problem!-- why is it that forklift trucks have a huge battery, but the voltage is limited to 55 volts?its because anything higher than55 is considered harmful-- on the other hand, if you were to link say-12 x12 volt car batterys in a "daisy chain ,then touch the ends you would get a big shock as you would be getting at least 150volts ,potential(12 batterys x12 -13 volts=144-152 voltsa 12 volt battery is actually13+volts) and that is high enough to carry some current through your body

as for the screw in lamps -get a smear of grease even vasiline onto the thread even though it melts with the heat it still helps

Edited January 11, 2005 by andy50

[Welsh John]

as for the screw in lamps -get a smear of grease even vasiline onto the thread even though it melts with the heat it still helps

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Would Preperation H be ok???

[andy50]

as for the screw in lamps -get a smear of grease even vasiline onto the thread even though it melts with the heat it still helps

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Would Preperation H be ok???

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lol!even some ky gel is worth a go w/john--(i hope your no into screwing light bulbs into your ring piece btw!!

[jackr]

Not to start a p*ssing contest but ....

How many times have you tightened the leads to your car battery and never felt a thing.

You only feel something if you complete the circuit, which is why one takes care to never make electrical contact with the car chassis while handling the hot lead.

I will absolutely guarantee you that if you grab the hot side of the battery with one sweaty hand and place your other sweaty hand on the engine block, then you are going to be in for one very unpleasant surprise (assuming a normal battery with decent cold-cranking amps, of course).

The point I was making was an electrical supply needs sufficient voltage to be harmful.

Again, this is nonsense. You are confusing voltage with EMF (or eletro-motive force). They are related but are not the same.

Here is a simple example to the contrary of your point.

If you go into any major telephone or ISP central office or head end, all of the mission-critical gear will have a central 48VDC battery backup (in addition to a gennie and other things). In some CO's, I've seen batteries stacked high and deep enough to fill a 20ftx40ftx10ft room (that's 8000 cubic feet of batteries). Larger CO's will have even more.

While still only a 48VDC supply, this amount of batteries stacked in parallel, the battery farm is typically capable of providing literally hundreds of amps of current, quite easily enough to zap anyone into next week or the next life.

Relatively little voltage .... but gobs and gobs of EMF. Easily enough to kill or at least ruin your day if your body happens to complete a circuit with it.

You're getting there if you're just starting out in simple physics, Spee, but a little way to go yet.

I kept the physics simple on purpose. Not to pontificate, but given that I have an undergrad degree in physics and have done quite a bit of electrical design, I'm pretty sure that I know what I'm talking about.

Cheers ...

Spee,I think you will find that Jackr is a sparky by trade with plenty of hands on experience and earns his living this way

I know who I would take my advise from.

Cheers, Chuchok

I'm actually a Plant Engineer by trade which is to do with industrial machinery and electrics on my part. I used to design and build control panels for refrigeration systems and repair food production machinery. Done a fair bit of house bashing as well but that's the easy stuff.

I'm sure Spee's a nice bloke and all that but maybe he's a bit too knowledgeable and losing sight of the basics. Anyway, mai pen rai as the saying goes.

[jackr]

voltage carrys the current(amperage)the higher the voltage-the more amps will be carryed,and so-more lethal -

if you touch a 110 volt cable, you will only recieve about half the current than you would if you touched a 240 volt cable -i worked at a new marks and spencer store as an electrician last year(in uk)

2 guys were working in the mains room,the large armoured cable they were terminating became live--415 volts, killing one guy and seriously burning tother --not good!

Not true! The higher the voltage the less the ampage (voltage and current are inversely proportional).

Consider the formula - I = W/V. Amps = Watts over Volts.

If you have a 1,000 watt heater in los (highly unlikely unless in the mountains in December) and the voltage is 240, thus 1,000/240 = 4 amps roughly.

If you have the same heater in the States - 1,000/110v = about 10 amps, therefore half the voltage, double the ampage. But even when you have double the current in the States you're more likely to die from a fault on the los heater due to the voltage, or charge, being higher.

Another example would be a typical car battery able to dish out about 50amps but you certainly won't get killed even if you grab the positive and stand in a puddle of water because the charge is minimal.

But it's incorrect to think you will die, period, if you come into contact with high voltage because it also needs a substantial current (oomph) to be lethal. Insectocutors run at about 5,000v and inadvertently touching a bar on one of them (not recommended) will certainly give you a kick and will blacken your finger but more than likely won't be lethal, unless you have a foot in water.

With you're above example about the 415v pisser, you have a much greater chance of dying because it involves two or three phases (lives) to a machine and can draw exponentially more current. Even so, you won't necessarily be killed period, it all depends on the current it may be drawing and if it all goes through you or you just receive a taster.

Anyway, yes, Thai wiring is horrendous - seeing their sparkies (electricians) connecting cables when they're live, even when it's raining, beggars belief!

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hi jackr, i agree with you ,you must have misunderstood my post ,im not too good at explaining myself! the higher the voltage is the higher the amount of current will be, passing through the person on thr recieving end -as for feeling a shock from a 12 volr car battery --ridiculous--the voltage is way to low to carry enough current through your body-even the 45 volts mentioned is still safe to touch with no flow of current through the body

in the iee regs (uk)any voltage up to 55 volts it considered safe

Sorry to sound patronising there, Andy. The point I was making was if you have the same piece of equipment able to run at different voltages, when it runs at the lower voltage the amps will be higher at the same wattage. You're right, the higher the voltage and current, the more lethal, and 415v at a couple of amps will throw you across the room, not to mention when it's kicking out something like 100A. OUch!

Happy New Year!

[aletta]

When you plug an appliance into a socket at the in-law's house you get a mini firework display and no-one bats an eyelid.

[RDN]

When you plug an appliance into a socket at the in-law's house you get a mini firework display and no-one bats an eyelid.

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"Famous last words" ??

[Spee]

I'm sure Spee's a nice bloke and all that but maybe he's a bit too knowledgeable and losing sight of the basics. Anyway, mai pen rai as the saying goes.

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Back at ya with those sentiments ...

Looking back in the thread my comments were unfairly harsh. My apologies for them.

Cheers!

[Welsh John]

as for the screw in lamps -get a smear of grease even vasiline onto the thread even though it melts with the heat it still helps

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Would Preperation H be ok???

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lol!even some ky gel is worth a go w/john--(i hope your no into screwing light bulbs into your ring piece btw!!

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Nothing like that Andy,It comes in handy the day after the night before binge on Thai food that has plenty of power & sends plenty of burning shocks to certain muscles!!!

Another thought came to mind though.Would the dry Marigold Gloves from the kitchen provide adequate insulation for a light bulb change???

[andy50]

as for the screw in lamps -get a smear of grease even vasiline onto the thread even though it melts with the heat it still helps

<{POST_SNAPBACK}>

Would Preperation H be ok???

<{POST_SNAPBACK}>

lol!even some ky gel is worth a go w/john--(i hope your no into screwing light bulbs into your ring piece btw!!

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Nothing like that Andy,It comes in handy the day after the night before binge on Thai food that has plenty of power & sends plenty of burning shocks to certain muscles!!!

Another thought came to mind though.Would the dry Marigold Gloves from the kitchen provide adequate insulation for a light bulb change???

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now your being perverse w/john!

[Jockstar]

I'm a sparky. When i walk around BKK. I am always amazed by what i see. What cracks me up is some sites have a big sign outside. It says. SAFETY FIRST! Ye fukcing right! Safety last. Get the job done and quickly. FIRST!

[britmaveric]

Wiring at its best:

Properly Maintained Wiring!

Add Watch your head to the cautions!!!

Edited January 12, 2005 by britmaveric