Standard LED bulb connected to a dimmer
- Thread starter Diyisfun
- Start date
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a) It will work.
b) It will not work.
c) Neither of the above.
d) All of the above.
a) No.
b) Yes.
c) Neither of the above.
d) All of the above.
a) Yes.
b) No.
c) Neither of the above.
d) All of the above.
Mixing LED drivers ( the bit in the lamp that controls current through the LED element ) and dimmers is a nightmare. Even when lamp and dimmer have been bought from the same source there is no guarantee of success, especially if the source has no technical support department.
To dim an LED the LED driver in the lamp must be able to control and vary a smooth steady current through the LED element.
The only way to dim LED elements is to reduce the current through them without using pulse width modulation ( PWM ). If pulse width modulation is used the LED appears to be as bright as the high current pulses and thus much brighter than the average current would suggest it would be.
Most dimmers control the voltage by PWM of the output at 100 pulses per second. An LED driver can become unstable when fed with pulses of power instead of a continuous supply.
Pulsing LED elements rapidly is the method used to obtain a bright light with minimum power consumption.
To dim an LED the LED driver in the lamp must be able to control and vary a smooth steady current through the LED element.
The only way to dim LED elements is to reduce the current through them without using pulse width modulation ( PWM ). If pulse width modulation is used the LED appears to be as bright as the high current pulses and thus much brighter than the average current would suggest it would be.
Most dimmers control the voltage by PWM of the output at 100 pulses per second. An LED driver can become unstable when fed with pulses of power instead of a continuous supply.
Pulsing LED elements rapidly is the method used to obtain a bright light with minimum power consumption.
duplicate post removed
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As helpful as ever.
It is helpful. Anything could happen, or not happen.
If you had asked "what would happen if I connect a 230v cob dimmerable LED light to a compatable dimmer " then the answer would be that you will be able to dim the lamp.
Using terms like "Standard LED bulb" and " a dimmer" gives no information.
Its like saying, "if i drive out of my house will I be able to get to Glasgow"
The answers are many and variable.
It is helpful. Anything could happen, or not happen.
If you had asked "what would happen if I connect a 230v cob dimmerable LED light to a compatable dimmer " then the answer would be that you will be able to dim the lamp.
Using terms like "Standard LED bulb" and " a dimmer" gives no information.
Its like saying, "if i drive out of my house will I be able to get to Glasgow"
The answers are many and variable.
eventually, but would I want to go there
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It may seem odd but with a cheap LED unit it would likely work. The problem is we are not buying a LED but a LED with some circuit to control the current. So consider cheapest of the cheap 9 LED's at 2.5 mA each in series with a full wave rectifier and a 87k Ω resistor.
If the root mean squared voltage is reduced it will clearly dim.
Then take a LED unit with a switched mode controller rated 150 - 250 volt with these until the voltage is reduced below 150 volt the controller would not affect the output.
However any controller chip needs power to run so at the point where the built in power supply can no longer smooth the supply to the controlling chip it will become unstable. When it becomes unstable it may fail or shut down. If it fails it may blow the LED it was controlling if it shuts down then once power is returned it may work again.
One may get flashes as the smoothing capacitor charges then as it starts to work quickly discharges.
The problem is you don't know what damage is being caused if any so a LED designed to 100,000 hours could fail after 50 hours or 5 hours or 500 hours you just don't know.
I can see the point of the question I have units which are designed to DIM and work with a remote control and it would be nice to run standard lamps off them.
However even the plug in type seem to have a minimum wattage as well as maximum and most LED bulbs are below the minimum voltage. I searched for my mother so she could control the lights from her bed. In the end I built a cheap plug in two way light unit with switches at door and bed and abandoned using the main light.
Maybe too basic for most people but even when you dim a LED the colour stays the same so no ambiance so easy way is to control how many rather than the output of each lamp.
But yes it does seem manufacturers are stuck in the 20th century and many of the automated lighting systems also include dimmers which now precludes their use.
If the root mean squared voltage is reduced it will clearly dim.
Then take a LED unit with a switched mode controller rated 150 - 250 volt with these until the voltage is reduced below 150 volt the controller would not affect the output.
However any controller chip needs power to run so at the point where the built in power supply can no longer smooth the supply to the controlling chip it will become unstable. When it becomes unstable it may fail or shut down. If it fails it may blow the LED it was controlling if it shuts down then once power is returned it may work again.
One may get flashes as the smoothing capacitor charges then as it starts to work quickly discharges.
The problem is you don't know what damage is being caused if any so a LED designed to 100,000 hours could fail after 50 hours or 5 hours or 500 hours you just don't know.
I can see the point of the question I have units which are designed to DIM and work with a remote control and it would be nice to run standard lamps off them.
However even the plug in type seem to have a minimum wattage as well as maximum and most LED bulbs are below the minimum voltage. I searched for my mother so she could control the lights from her bed. In the end I built a cheap plug in two way light unit with switches at door and bed and abandoned using the main light.
Maybe too basic for most people but even when you dim a LED the colour stays the same so no ambiance so easy way is to control how many rather than the output of each lamp.
But yes it does seem manufacturers are stuck in the 20th century and many of the automated lighting systems also include dimmers which now precludes their use.
Not if the dimmer requires a load >than 40W it will probably not work.
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Agreed but latter I did go in to minimum wattage. At 0.58W I am sure a simple wire wound variable resistor would do the job. 50kΩ should work fine.
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