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[advise me] Add resistor2lower 240Vac so that bulb not blow?

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Angie_MY

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hi. my mum urged me to do a project for her..

she like to use these bulbs for chinese tradisional pray purpose. these bulbs will always be on for 365x24x7.. but the problem is, the bulbs always blow up, and need a new one to replace..

what i suspect is, this is normal bulb, not led type, therefore, it generate lot of heat, and 24x7 will kill the bulb fast..

therefore, i am thinking to add in a resistor to low down the supplied voltage. (my house use 240Vac supply.) main reason i choose resistor is, i have a few 5W resistor with me.

180 Ohm 5W
330 Ohm 5W
8k Ohm 5W
10k Ohm 5W

before i start the modification of power supply, i need confirmation from expert here. would my idea work? which resistor more suit my need? or any better idea?

thanks.\]
 

Re: [advise me] Add resistor2lower 240Vac so that bulb not b

Hi,
Can try with a suitably rated diode in series with the lamp and use a doubly rated lamp, Else try for an LED lamp.

Regards,
Laktronics
 

resistor is not recommended in this case?
 

Re: [advise me] Add resistor2lower 240Vac so that bulb not b

Hi,
Resistors with appropriate wattage should work, but they waste power and gets hot, diode only blocks voltage and does not waste power. You may get light dimmers or for zero watt (15W) bulbs, normal electronic fan regulators may work, I have no experience in such applications.

Regards,
Laktronics
 

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    Angie_MY

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Re: [advise me] Add resistor2lower 240Vac so that bulb not b

Hi,

You may simply connect two lamps in series so that the voltage is shared equally and the current is reduced but at the cost of reduced brightness.
 

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    Angie_MY

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Re: [advise me] Add resistor2lower 240Vac so that bulb not b

laktronics said:
Hi,
Resistors with appropriate wattage should work, but they waste power and gets hot, diode only blocks voltage and does not waste power. You may get light dimmers or for zero watt (15W) bulbs, normal electronic fan regulators may work, I have no experience in such applications.

Regards,
Laktronics
Click to expand...

so, the best solution is still to use led bulb.
led generate minimum heat, very less chances to blow...

anyway, thanks. i will buy led bulb for my mum. hope i could find them on my local market..
 

If you cannot buy led bulbs locally, Matbob's 2 bulbs in series is the best idea. They will last a very long time.
 

urgh...
the LED bulb is sold at about USD$10 at my local TESCO store.. while what i normally use was just USD$0.30 only..

well, i am thinking if i add capasitor in?
 

Re: [advise me] Add resistor2lower 240Vac so that bulb not b

Angie_MY said:
urgh...
the LED bulb is sold at about USD$10 at my local TESCO store.. while what i normally use was just USD$0.30 only..

well, i am thinking if i add capasitor in?
Click to expand...

since you think the LEB bulb is expensive.. and also, in my humble opinion, you could actually expect the LED light also would never as bright as the bulb you currently using. so, no point to use LED bulb if you want the brightness.

serial connect of 2 bulbs would be the best choice in your case..
 

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    Angie_MY

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