Today I put up some incandescent Christmas lights in my room and for some reason every time I light up my electronically driven fluorescent lamps they start having a seizure and flicker violently.  Why does that happen and can I prevent it from happening? 

This is a sign that there is a significant chance of a fire hazard.

If turning on one load will cause severe flickering in another load, it means that there is too much resistance in the cable somewhere. Usually this means a wirenut that came loose or a shoddily connected outlet. Resistance = voltage drop. Voltage drop = heat. Heat = fire risk.

You can verify this by turning on the christmas lights, and then putting an electric heater or kettle on the outlet you normally use with the fluorescents. The lights can dim slightly, but any flicker is a sign of a true fire hazard.

I plugged in a 200w incandescent in the socket that the 40w fluorescent installation is plugged in usually and there was no difference or flicker from the Christmas lights. Could it be some Hz difference due to a faulty electronic ballast?

The fluorescent driver will either be good or bad, rarely something inbetween. If it lights up the tubes normally, it's good.

It's normal if you get one dip in the brightness of the christmas lights when plugging in, but that should last only a fraction of a second, and only be once.

Do the test as i suggested. Christmas lights as they were, big 1000-1500w load in place of the fluorescent lamps.

Still nothing Even with a 1500w load the incandescents have no problem and operate just fine, only with the fluorescents they start flickering for as long as the lamps are in operation and the moment I switch them off the lights just get back on track and start their casual dimming and brightening as they are intended.    

Christmas light effects box typically need some synchronization to line cycles to count effect timing and to sync SCR firing to line. Some cheaply made ballast may leak enough HF noise on the line line to screw up cheaply made effects. A capacitor in range of ~1uF 400V across power line may cure this.

Could be, since a small HDMI to AV adapter that is wired in the same power strip resets every time I switch on the fluorescents, the same thing happens when my phone charger doesn't make good contact with the plug and arcs (the adapter resets ).   

Allot of those little light-controllers can be dropped down quite a bit on voltage and still operate just fine (think like half-voltage)! So simply putting a larger load on the circuit should have zero effect - as you saw.


I would say its one of 2 things:

A ballast is backfeeding 'noise' onto the mains lines (it doesn't even have to be bad to do this, cheap low-quality ballasts simply may not be very 'clean'). Basically what RRK said, this can mess up the timing if the Christmas lights controller simply reads off mains frequency for it. (And if the controller has its own timing chip, the noise can still interfere with its running program)

Fluorescent ballasts can/do generate a fairly good EMF(electro-magnetic field) around them. If the controller for your Christmas lights is located near enough to the fluorescent to be within that EMF, it will cause the chips within it to malfunction

I'm assuming you have multiple fluorescents running?... try turning them on one at a time, its very likely only one causing the issue.

Probably that’s the main issue. Though since I have connected the two tubes in series and have mounted the wires it’s quite difficult for me to connect them individually. And also for the little adapter that I was talking about, well the computer is the issue. The HDMI output is so weak it could barely send a powerful enough signal to the adapter and recently it doesn’t output any signal which makes me think something might have been burnt up.

Aren't the curtains some of the "intelligent with remote control" type? Because then I would expect the fluorescent interfering with the control, causing it to wildly change modes so flicker. That coupling could even be optical: The resifue of the HF ballast flicker is enough to trigger the IR receiver and cause its output to toggle wildly. With very substandard signal identification routine in the LED curtain microcontroller it gets confused by it and responds erratically.

Generally I do not see how a fluorescent ballast can cause so huge interference to disturb something that is not especially designed to receive some RF or HF modulated IR signal, unless it by itself is not very cr**py design (improper supply filtering. bad CPU board layout, long wires to the LEDs connected directly to the CPU IC,...).

So most likely two s****y products met in one room, one overly emitting and one being overly sensitive...

Probably cheaply designed and manufactured products is the case. Though the computer problem is solved...... The video port burnt out completely and now I have no second monitor to use! Isn't that great ! The computer should be gleeful I didn't toss it out the window.