gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
161126-2031 EST
mark32:
Glad you had success.
.
mark32:
Glad you had success.
.
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Need fix for LED flicker, add a resistor?
- Thread starter mark32
- Start date
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Fnewman
Senior Member
- Location
- Dublin, GA
- Occupation
- Sr. Electrical Engineering Manager at Larson Engineering
Looks like 'problem solved' but for future use here is a link to the Feit lamp/dimmer compatability page. A good place to start!
http://www.feit.com/Dimmer_Compatibility
http://www.feit.com/Dimmer_Compatibility
JFletcher
Senior Member
- Location
- Williamsburg, VA
I was going to ask if there was any chance circuits were 'double dimmed', or where the dimmers were located in 3 way circuits, but with the problem solved....
gar
Senior Member
- Location
- Ann Arbor, Michigan
- Occupation
- EE
161127-1253 EST
I think it is useful that you provided the Feit reference, but I think the document is almost totally useless.
From the beginning comments:
All these exclusions really mean that you have to do trial and error anyway.
The document is way too complex, excess unnecessary detail and not the correct detail, to be of any use.
Fundamentally a phase shift dimmer applies power to a load during some one contiguous fraction of a half cycle and off during the other part of the half cycle. By design the on portion can be the leading part of the cycle, or alternatively the trailing part.
If I take an ideal source as per the previous paragraph and an LED does not dim as expected, then the problem is totally that of the bulb, and or in combination with external circuitry, but not the dimmer.
Such an ideal dimmer might be a three wire dimmer (one that requires a neutral). It is fairly clear that if the dimmer turns on at a voltage zero crossing and turns off at a controlled phase angle and after off with zero impedance, then the source is well defined and independent of the load.
To make an ideal dimmer that is off until some phase angle after the voltage zero crossing, then it is necessary to define what is to control the turn off point. In a conventional dimmer this is when current goes to zero. Therefore it is load dependent. If with this type of dimmer current never goes to zero before the next half cycle turn on point, then I would classify the problem as a bulb problem. It was not designed for this type of dimming.
If a bulb is to be defined as dimmable, then it should function as expected with one of these ideal dimmers for all dimmer settings. If it doesn't, then it should not be classified as dimmable.
Thus, it should be simple to select a dimmer and a bulb.
This means you need to know how dimmers work and are designed, and whether LED or CFL bulbs really do what their manufacturers claim.
.
I think it is useful that you provided the Feit reference, but I think the document is almost totally useless.
From the beginning comments:
Compatibility is based upon testing of a limited sample size conducted by Feit Electric in a laboratory environment -- field results may vary due to a number of factors.
“Compatible” means that the bulbs can be dimmed, although the LED lighting device dimming performance may not be the same or similar to dimming of incandescent or halogen bulbs, fixtures, and luminaires.
Some possible dimming variations include but are not limited to: less dimming range than an incandescent or halogen bulb; dimming less smoothly than an incandescent or halogen bulb; flicker or shimmer at certain light levels; and, buzzing or humming at certain light levels.
Dimming equipment, applications, installation, and conditions of use are many, varied, and beyond the control of Feit Electric and therefore Feit Electric does not represent or warranty the suitability of an LED lighting device for use with any particular dimmer. The warranty on the LED lighting device package is the only applicable warranty made by Feit Electric.
All these exclusions really mean that you have to do trial and error anyway.
The document is way too complex, excess unnecessary detail and not the correct detail, to be of any use.
Fundamentally a phase shift dimmer applies power to a load during some one contiguous fraction of a half cycle and off during the other part of the half cycle. By design the on portion can be the leading part of the cycle, or alternatively the trailing part.
If I take an ideal source as per the previous paragraph and an LED does not dim as expected, then the problem is totally that of the bulb, and or in combination with external circuitry, but not the dimmer.
Such an ideal dimmer might be a three wire dimmer (one that requires a neutral). It is fairly clear that if the dimmer turns on at a voltage zero crossing and turns off at a controlled phase angle and after off with zero impedance, then the source is well defined and independent of the load.
To make an ideal dimmer that is off until some phase angle after the voltage zero crossing, then it is necessary to define what is to control the turn off point. In a conventional dimmer this is when current goes to zero. Therefore it is load dependent. If with this type of dimmer current never goes to zero before the next half cycle turn on point, then I would classify the problem as a bulb problem. It was not designed for this type of dimming.
If a bulb is to be defined as dimmable, then it should function as expected with one of these ideal dimmers for all dimmer settings. If it doesn't, then it should not be classified as dimmable.
Thus, it should be simple to select a dimmer and a bulb.
This means you need to know how dimmers work and are designed, and whether LED or CFL bulbs really do what their manufacturers claim.
.
- Status
- Not open for further replies.