Re: LED dimmable bulbs with X10 switches

[Geoff <geoff@xxxxxxxxxxxxxxx>]

On Sat, 21 Feb 2015 17:33:48 -0800, "Bob F" <bobnospam@xxxxxxxxx>
wrote:

>Geoff wrote:
>> On Sat, 21 Feb 2015 11:03:33 -0800, "Bob F" <bobnospam@xxxxxxxxx>
>> wrote:
>>
>>> Bob F wrote:
>>>> I just bought some Cree LED soft white "60W" "4FLOW filamant design"
>>>> bulbs.
>>>> On one circuit, with just one bulb, the bulb lights at a mid level
>>>> when off or full brightness when switched on at the switch. The
>>>> switches involved are the old X10 switches with a lower section that
>>>> slides to the left to cut off all power. The problem is that the X10
>>>> controller cannot turn that bulb either on or off. Turning other
>>>> circuits using the same controller continues to work fine.
>>>> On another circuit, there is a 2 bulb fixture downstairs and a 2
>>>> bulb fixture upstairs, all currently incandescent bulbs. If I
>>>> remove one of the incandescent bulbs downstairs and replace it with
>>>> the LED bulb, everything works OK, with the incandescent bulbs
>>>> dimming much more than the LED bulb when the dimming function is
>>>> used. When I removed the downstairs incandescent bulb,leaving the
>>>> LED bulb, again I could not control the lights with the X10
>>>> controller. This is despite the 2 incandescent bulbs in the
>>>> upstairs fixture.
>>>> Has anyone here seen similar problems, and come up with any
>>>> solutions to them?
>>>> I do realize that the low brightness issue in the off position of
>>>> the initial circuit is do to the switch sense feature of the X10
>>>> switches, and that the incandescent bulbs in the second circuit
>>>> eliminate that problem there.
>>>
>>> I just tried the second circuit again, and it seems I can turn in
>>> off with the controller, but not on.
>>>
>>
>> You are dealing with a limitation in the triacs in the X10 that switch
>> the current to the load on and off. There is a minimum sustaining
>> current that a triac needs to keep itself on after it's been fired by
>> the trigger circuit. Replacing an incandescent with an LED can put you
>> below that minimum current and cause the triac in the X10 module to
>> turn itself off.
>>
>> The load required by an X10 dimmer varies with the manufacturer but
>> what I've found during a quick google search is a 40W minimum might be
>> typical. At 120VAC this means the minimum load current needs to be
>> around 0.33 Amps.
>>
>> With LED technology you need to ignore the "wattage" of the bulb since
>> it's an equivalent rating, not a power consumption rating. A Cree 60W
>> equivalent bulb uses only 9 to 9.5 Watts in the soft-white and
>> daylight types and that's less than 0.08 Amps at 120 volts, a very
>> economical current indeed and about 4 times less current than a 40W
>> incandescent will draw.
>>
>> If it's a multi-bulb fixture you can add three more LED bulbs to get
>> the total current up into the sustaining range of the X10 but it may
>> be more economical to use an appliance module instead. It uses a relay
>> and you lose the dimming capability and the "all lights on" capability
>> but if remote on-off is your desire then it's definitely preferable to
>> loading up on LED's just to get back into the higher current draw that
>> LED's are supposed to be avoiding.
>>
>> P.S. I love my Cree LED bulbs and I've made it my goal to replace all
>> my incandescents with Cree bulbs as the incandescents burn out.
>
>The switch at the wall has no trouble turning them on and off. It's only the
>remote control that has the problem, which would make me think it's a
>communication problem rather than a triac holding voltage problem.
>
>I did just go try the bulb in another lamp controlled by an appliance module.
>Interestingly, this bulb did not glow when off like the other LED bulb that had
>been in that lamp. It also switched on/off remotely just fine.
>
>Wierdness!
>

Yes, that you will get weirdness when running X10 units without a
minimum load is well-documented for years.

http://www.electronicproducts.com/Power_Products/Power_Management/Efficient_dimming_for_LED_lighting.aspx