What are the real dangers of putting a higher wattage bulb into a lower wattage light fixture? I assume that an overload can cause some sort of meltdown or electrical fire, but is it really all that bad to put a 75w in a 60w? What about higher spreads? I’ve put 100w bulbs in 75w sockets often, and nothing has happened yet…Does it maybe affect the lifetime of the bulb or appliance, or what???
Thanks-
-Tcat
I have kitchen lights that specifically state do not use anything over 25 watts. Well, being the more power freak that I am, I put 40 watt bulbs in them and they lasted about a day. Not learning from this, I repeated it three times before I got the picture.
I think the wattage recommendation you get on table and standard lamps is to do with the maximum heat the lamp-shade can take.Put a too high bulb in the lamp and you could melt the shade or even cause it to catch fire.
The warning really should read “Danger: to avoid risk of lawsuit…”
The manufacturer is (for the most part) thinking about the size of the lamp and what kind of shade you are likely to put on it. A small lamp only about 12 or 18" high is going to get a little tiny lampshade of the sort that boozers like to wear as hats. With such a small shade being so close to the lamp, the manufacturer doesn’t want you to risk a fire in your house, which may lead to an unpleasant lawsuit against the lamp maker.
Recessed lighting fixtures also have these notices, because they have metal bodies and tranfer heat directly to ceiling materials like sheetrock, wood & insulation.
The actual electrical contacts (porcelain socket & wiring) are pretty statnard for a wide range of household fixtures. The tolerance of those parts doesn’t come into play until you start getting into heavy duty stuff like heat lamps & such.
A few years ago, in the beginning of my electrician apprenticeship i was taken to a house that burned down. The decided cause of the fire was a 150 watt bulb is a lamp that was not designed for it. It definatly made an impression on me seeing the childrens clothes and dolls melted and charred. The odd part was the room that the fire started in wasnt nearly as burned as the rest of the house (which was knocked down after the investigation was completed) sooo back to the original topic. To use a higher wattage bulb than the fixture is “rated” for is a fire hazard. Please dont do it…
-me
Another thing to watch is to make sure that the bulbs you fit are fused.Here in the UK you can buy very cheap bulbs made in obscure Eastern European countries.Most of these bulbs do not have an internal fuse.When the bulb finally expires it can cause an short circuit within the bulb.without this internal fuse you can trip your main lighting circuit or worse. In my case I lost two dimmer switches destroyed by these short circuits.I see bow that some dimmer switches now have thier owm fuses to guard against this.
For “bow” read “now”.Dyslexia rules ko.
The bulbholder is constructed of materials which are designed to withstand heating and cooling effects up to a maximum value.
Usually at 150W or above lampholder will be made of ceramics.
Some lampholders will also dissipate heat, the brass ones in particular. This allows the bulb to run at a lower temperature. Anyone who has lights in overly warm environments will know that these blow more often.
Being able to dissipate heat is also important for maintaining integrity of the wiring insulation which is usually pvc, though I have seen silicon rubber in high temperature applications.
I’m a little surprised that anyone would need to use 150W bulbs anyway since there are high light output lamps that consume far less current.
Encapsulated halogen lamps typically use less than half the current for the same light and there are versions which look virtually identical to the ordinary bulb.
If you need more light than the maximum rating of the lampholder it would be far safer and economical to use either halogens or the self contained flourescants that plug straight into standard lampholders.
There is no need to put yourself or your property at risk, especially when the alternatives will do exactly what is required.
Allow me to emphatically agree with what mikey07005 and casdave have said. The electricians are the experts here, and there is a fire hazard if you exceed the recommended wattage.
Personally, I use fluorescents of the same wattage as the rated incandescent if I need more light from a socket. They put out over twice the light for an equivalent wattage and are more common than screw-in (Edison base) halogens are around here (these things are pretty much a resistive load …right?)
I’m still noodling over what David Cronan said about making sure my bulbs are ‘fused.’ I live in the US, where things are a bit different from things in the UK I guess, but I’ve never heard of a ‘fused’ light bulb.
Being the destructive cretin my friends have come to love and give a wide berth to, I’ve mashed many a light bulb during my formative years – 46 formative years so far – and I’ve never seen anything like a ‘fuse’ or a fusible link, other than the filament itself. Have I missed something here?
When a light bulb ‘blows,’ isn’t it because the filament has separated due to heat or jarring, and doesn’t that separation, in and of itself, act as a sort of ‘fuse,’ breaking the circuit and thus the current flow? How can a ‘blown’ light bulb, i.e. one through which no current passes, destroy a dimmer switch?
I will say that most of the bulbs I’ve mashed contained a molded glass insert sprouting from the base of the bulb that served to separate the relatively heavy, stiff wire leads that support the filament and connect it to the circuit. But that’s not a ‘fuse.’ It’s a structural support, and a dielectric element, not the stuff of a ‘fuse.’
My dad once served as a volunteer fireman back when firemen would actually make house calls to change blown fuses and such. (He had a small box full of ‘emergency’ pennies he had removed from the sockets of blown fuses.) He took a call once from an elderly lady who complained that her electric bill was too high, and wondered if a fireman could come to her house to check her fuses, etc. Before Dad could get out the firehouse door, the lady called back, explaining that she’d found the problem. She remembered that her hall closet light bulb had ‘blown’ and she’d removed it, but she’d forgotten to turn off the light switch. Thus, the ‘juice’ was pouring out of the empty socket, I suppose, to waste itself on the floor.
Art Linkletter was right – People Are Funny!
When an incandescant lamp blows the filament it sometimes sticks the filament remains across the terminals but now instead of being a carefully manufactured item its just a molten strip of metal, which then acts as a short circuit this is what causes circuit breakers to trip.As soon as it cools the molten strip hardens, shrinks and severs.
I can’t say I’ve met bulbs with fusible elements but if there were they would be in the base or possibly in the glass filament supports and would not be at all obvious.
To quote the packaging on my light bulbs “internally fused for extra safety and reliability”.Most of the light fittings in the UK are of the “Bayonet Cap” type where you push and twist the bulb into the fitting.The electrical contact is through 2 spring-loaded pins in the fitting.If these springs get weak over time then you can get arcing and the light starts to flicker.I suppose you will get the same affect on US fittings if the bulb is not screwed in tight enough.
No comment on internal fusing on our (US) bulbs. Then again, our house current is at 115VAC, so the bulbs are designed differently, and probably have stiffer leads going up to what may be a longer(?) filament.