Operating CFL's with electronic control gear at reduced voltage kills them. I discovered this while repairing a couple of them. Running via a current limited power supply and lower voltage while testing them revealed the switching transistors getting very hot. I couldn't see anything wrong so applied full mains voltage and everything ran cool. Obviously at lower voltages the transistors were not being driven into saturation.
The point is don't run them on a supply of less than 340V peak...light dimmers and square wave inverters with a 240V peak output. The original Philips CFL's with a proper iron cored choke were much more immune to this sort of thing but don't seem to have been available for quite a few years.
