Can dimmer units control modern fluorescent light?

[MindBender]

I know the usual answer to this question is 'no'.

Here's explained how it works: A classic fluorescent lamp uses a clever trick with an induction coil, a 'starter' and glow wires in the lamp to get itsself ignited. When the lamp is powered on, the 'starter' gets full voltage, making it short its terminals. This will send a high current through the glow wires in the lamp itself, while this high current also charges the induction coil with a magnetic field. Shortly after that, the 'starter' will un-short its terminals. This will make the induction coil discharge and becuase it's serialized with the mains voltage, the discarge voltage is added to the mains voltage to about 600 volt. This 600 volt, together with the heated up glow wires, is enough to ignite the lamp.

Modern fluorescent lamps, especially the screw-in replacement lamps, have electronics to generate the ignition voltage. This is more energy efficient and it extends the lamps life.

Has anybody tried if it works? I know the lamps probably cannot be dimmed, or in the best case only after they have been ignited at full level first. Can the soft start/stop as present in most dimming units, be disabled?

[Han]

I have tried several types of lamps.
1) To be save: switch all types of fluoricent lamps with an X10 appliance module (So a unit that contains a relais).
2) If you realy want to use a unit with a triac output for controlling fluricent lights (units that are capable of dimming have a triac output) do not use a dim level, just turn it ON or OFF. With most units this is not possible because of the soft start and stop.
I build my own X10 units and I spoiled quite some triacs in the proces of selecting the right triac and finding the correct way of biasing the triac for fluoricent lights and electronic transformers.

Han Alink

[MindBender]

Thanks for your very useful answer. So finding the proper triac isn't an easy task. Would that be because of the high rush-in current, the current that's both heating the filaments and charging the inductive coil? Because those aren't present in modern light bulb replacement lamps (Dutch: Spaarlampen). And those are the ones I'd like to use. I've figured that installing X10 modules would be a good oppertunity to install dimmers everywhere instead of switching units. But I have also installed these energy saving lightbulbs everywhere. Of course I could change them back to regular light bulbs, but I don't want that.

[Niknik]

What about those high-requency fluorescent lamps?
I had several dimmable ones a few years ago (had a specific controller)... Anyone know how we could interface those with a x10 module to do the dimmming?

[Han]

Most problems are associated with the way of operating the triacs. Read this article:

<b>Download Attachment:</b> [img]images/icon_paperclip.gif[/img] triac sturing_2.pdf<br />94.67 KB

For my own X10 designs I always use the method described at page 7,8.

Han Alink