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NinjaYeti
Jul 25, 2014, 07:12 AM
Hi,

Firstly, please excuse me as I've zero knowledge when it comes to electricity and lightbulbs in particular.

I live in Singapore, where the voltage is 240V. I recently bought a lamp from the US that operates at 110V. There was a bulb that was included together with the lamp.

I've plugged the lamp into a converter that converts a 110V appliance to run from our 240V wall power outlets.

After about 4 months of use, the light has since blown and I'm wanting to get a replacement lightbulb.

Now, because it's a 110V lamp, do I buy a new 110V bulb or a 240V bulb.

Was there a reason why the bulb lasted for only such a short period?

Now, do I a new 110V bulb or a 240V bulb?

Thanks

smoothy
Jul 25, 2014, 07:47 AM
Depends on what kind of lanp it is... Is this fluorescent, incandecent, halogen? I have to ask because bulbs are typically not incluided with lamps, and there are a number of different types, some with ballasts that NEED the correct voltage.

NinjaYeti
Jul 25, 2014, 08:12 AM
Thanks, it is an incandecent lightbulb.

smoothy
Jul 25, 2014, 08:32 AM
Regualr size lamp that screws in like you would have anywhee else in your house or apartment?

If so you can probibly use a regular bulb in your local votage without the transformer as long as you don't exceed the wattage the lamp is desinged for (it shoud tell you the maximum wattage on a label).

If you use compact fluorescent lamps or the newer LED lamps... you aren't going to be exceeding the lamps rating as both of those generate less heat and draw less current than an incandescent bulb with the same light output.

NinjaYeti
Jul 25, 2014, 09:20 AM
http://www.whichledlight.com/content/images/shapes-sizes.jpg

Yup, the bulb is pretty much like (C) Candle.

So you're saying I can use a regular bulb in 240V and not use the transformer?

But isn't the wiring in the lamp unit itself set to 110V?

Sorry if I'm asking a silly question.

Thanks!

joypulv
Jul 25, 2014, 09:49 AM
An incadescent bulb for 110v will use 4 times the wattage. It will be bright and it's life time will be shortened considerably, as you discovered. Get a 220 rated bulb, I assume, and bring the burned out 110 one with you to match the base.

smoothy
Jul 25, 2014, 10:17 AM
The wiring was for 110v, but for an example , a 220v bulb of any given wattage, will use half the current of a 110v bulb of the same voltage. Which means the wiring will not be overloaded.

Votage X Current = Watts.

a 220v bulb of the desired wattage (within the design limits of the lamp) will work.

donf
Jul 25, 2014, 02:13 PM
Why are you even having this discussion? Please consider using the devices that are designed for your electrical system, particularly if you are a permanent resident.

NinjaYeti
Jul 25, 2014, 06:03 PM
@smoothy & @joypulv,

Thank you for your replies. I will purchase a 220V bulb. That's all I needed to know. :)

hkstroud
Jul 26, 2014, 07:01 AM
I am going to agree with Don. You really should be using the appliance as it is designed unless you are a qualified electricial engineer.

I agree with Smoothy that the amperage draw will be reduced and the risk of over heating is also reduced. But the voltage rating of the internal wiring is based on the type and thickness of the wiring insulation. All house wiring in the US is rated up to 600 volts but I don't know that that is true for the internal lamp wiring or any switches or other devices that may be in the fixture.

So, unless you disassemble the fixture and verify the voltage rating of the internal wiring, I agree with Don. Use the fixture as designed.

While the your regular 240V bulbs may appear simular to the 120V bulb most likely they will not fit. At least I hope not.

NinjaYeti
Jul 26, 2014, 08:20 AM
Thanks for your reply hkstroud.

So in another words, if I understand you correctly, it's best for me to continue to use a 110V bulb as it is designed for the appliance?

It's pretty much going to be impossible to find a 110V bulb in a country that 220V exists in.

I did see a bulb today that was 160V-220V. Will this make any difference as it has a 'lower' voltage rating than 220V, but still not as low as 110V?

Thanks for your help :)

donf
Jul 26, 2014, 08:33 AM
You have totally missed the meaning of my response.

Here in the U.S. we use a 120/240 volt 60 Hz. System. In order to convert components or supplies (120 Vac light bulbs) to be used on a 240 Vac system, you have to step the voltage down from 240 volts and manipulate the freq. of your electrical if it is different from 60 Hz.

The transformer that the appliance was connected to is doing the manipulation, not the bulb!

Without that transformer, you would be putting 240 volts into a device that is designed for 120 volts. Disaster!

Your country's supplies and devices are designed around a 240 Vac system and work out of box without having to manipulate the base electrical supply, so why do it?

Simply purchasing a 240 V will not solve your dilemma. The bulb you were using was placed into a socket designed for a 120 Vac device. A 240 Vac bulb's base is not the same size as a 120 Vac bulb's base. And even if it does fit the socket, it will not give off the correct amount of lumens because you are cutting the voltage to it by 50%!

NinjaYeti
Jul 26, 2014, 08:47 AM
Hi Donf,

Thanks for your reply and effort to explain it better to me.

The reason why I use the said lamp is because it's not readily available nor sold in any other country other than the US, therefore being only ever a 110V appliance. It's also a lamp that my wife loves as it's from a character from a series she adores, so there's really no substitute for it other than to buy a 110V version and using a transformer.

Having said that, it seems that you are strongly recommending as with hkstroud, to use a 110V bulb, which is impossible to find in Singapore.

So since you said that the transformer the appliance is connected to is doing the manipulation and not the bulb, if I bought a 160V-220V bulb that I saw in the shops today, the bulb would run at a lower 'rate' and last longer and won't be as bright?
Would the bulb operate at 160V because it's the lowest to 110V?

(The lamp's main purpose is currently as a night light, so being dim is actually good)

Thanks

hkstroud
Jul 26, 2014, 09:03 AM
It's pretty much going to be impossible to find a 110V bulb in a country that 220V exists in.

My suggestion would be the internet. What you need to know is the wattage, the shape and the base.

The wattage should be shown on the existing bulb and is probably either 40 or 60 watts. The shape is obvious but you can change if you would like. The base size, from your description, would be candelabra. Your present bulb may have a model number stamped on the base.

Here is a link to Home Depot, which is a US national building supply. It is where all us home owners go to do our fix it up task. You can certainly order a replacement bulbs on line but I don't know if Home Depot ships internationally. If they do the shipping cost should be minimal.

Decorative Light Bulbs - Light Bulbs - Electrical at The Home Depot (http://www.homedepot.com/b/Electrical-Light-Bulbs-Decorative-Light-Bulbs/N-5yc1vZc7n7)

You said that the bulb that came with the light lasted about 4 months. The average life span of a incandescent bulb is about 760 hours. At 6 hours per day for 120 days, that is about right. Once you are certain that you have selected the correct bulb, order a life time supply, they are relatively inexpensive.


(The lamp's main purpose is currently as a night light, so being dim is actually good)

Based on that comment, you probably want a 15 or 25 watt bulb. Here is link to a 15 watt, double life, candelabra base bulb.

http://www.homedepot.com/p/GE-Crystal-Clear-Double-Life-15-Watt-Bent-Tip-Decorative-Candelabra-Base-Incandescent-Light-Bulb-4-Pack-62072/202529952?N=5yc1vZc7n7